New User Registration

In order to register on this site, you must first submit the passphrase below.

2002 - 9/10/11 Joint Meeting with Belgian Psychological Society, Leuven, Belgium
Article Index
2002 - 9/10/11 Joint Meeting with Belgian Psychological Society, Leuven, Belgium
Page 2
page 2
All Pages

LEUVEN MEETING 2002

A joint scientific meeting with the Belgian Psychological Society held at the Department of Psychology, University of Leuven, Belgium, 9-11 April, 2002.

 

Tuesday 9 April 2002, 9:30 - 11:30

Symposium 1 - Spoken Word Recognition
Convenors: James McQueen and Anne Cutler, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands; Alain Content, Free University Brussels, Belgium

Perceptual assimilation and lexical access.
Uli H. Frauenfelder, Pierre Halle, and Juan Segui, University of Geneva, Switzerland and CNRS, University of Paris V, France

Is the syllable an intermediate representation in French speech processing? Evidence from form priming in nonwords.
Nicolas Dumay, University of York, United Kingdom

French speakers' syllabification of trisyllabic pseudowords.
Alain Content, Free University Brussels, Belgium

Lexical activation in spoken-word recognition: Insight from the pause-detection paradigm.
Sven Mattys, University of Bristol, United Kingdom

Lexical re-tuning of phonetic categories during speech perception.
Dennis Norris, Anne Cutler and James M. McQueen, (MRC Cognition and Brain Sciences Unit, Cambridge, United Kingdom and Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands)

Tuesday 9 April 2002, 9:30 - 13:00

Invited Symposium 1 - Visual Perception of Objects, Scenes, and Actions Commonalities and Distinctions
Convenors: Peter De Graef and Karl Verfaillie, University of Leuven, Belgium

Diagnostic recognition: A new informational framework for object categorization
Philippe Schyns, University of Glasgow, UK

The understanding of goal-directed actions: Functional neuroanatomy
Julie Grèzes, Wellcome Department of Cognitive Neurology, London, UK

fMRI investigations of high-level vision in humans: people, places, and things
Nancy Kanwisher, Department of Brain and Cognitive Sciences at MIT, USA

Tuesday 9 April 2002, 14:00 - 16:00

Symposium 2 - Prospective memory
Convenor: Géry d'Ydewalle, University of Leuven, Belgium

A prospective study of prospective memory: Challenges due to procedural changes for an fMRI study
Wim De Bruycker, Géry d'Ydewalle and Els Brunfaut, University of Leuven, Belgium

Activation of performed and to-be-performed activities in healthy and impaired older adults
J E Freeman and J A Ellis, University of Reading, UK

Event-based prospective memory in 3- to 9-year old children: The effects of age, explanation and type of action
L Kvavilashvili, D J Messer and F E Kyle, University of Hertfordshire, UK, South Bank University, UK and Royal Holloway, University of London, UK

Complex prospective memory development in children
M Martin, M Kliegel and J A Ellis, University of Heidelberg, Germany and University of Reading, UK

Tuesday 9 April 2002 14:00 - 16:00

Symposium 3 - Evaluative Conditioning
Convenors: Andy Field, University of Sussex, UK and Jan de Houwer, University of Ghent, Belgium

Visual Evaluative Conditioning and Contingency Awareness: Past Controversies and Current Wisdom
Andy Field, COGS, University of Sussex, UK

Evaluative learning that results from an aversive conditioning procedure: an overview
Dirk Hermans, Geert Francken and Debora Vansteenwegen, University of Leuven, Belgium

Associative transfer of non-evaluative stimulus properties
Jan De Houwer, Tom Meersmans, Frank Baeyens and Paul Eelen, University of Ghent, Belgium and University of Leuven, Belgium

The allocation of attention to stimuli imbued with valence through evaluative learning
Eamon Fulcher, Department of Psychology, University College Worcester, UK

Tuesday 9 April 2002 14:00 - 16:00

Symposium 4 - Eye Movements and Visual Cognition
Convenor: John Findlay, University of Durham, UK

Executive contributions to eye movement control
Timothy L Hodgson, Imperial College of Science, Technology and Medicine, Charing Cross Hospital Campus, London, UK

Exogenous and endogenous saccades: Effect of dual-task interference from an action representation based view
Els Stuyven, Department of Experimental Psychology, Ghent University, Belgium

Does scene context and fixation position affect the processing of objects in scenes?
Lynn Gareze and John M Findlay, Department of Psychology, University of Durham, UK

The visual analog in transsaccadic object perception
Peter De Graef and Karl Verfaillie, Laboratory of Experimental Psychology, University of Leuven, Belgium

Eye Movements in Reading: Word Frequency, Word Predictability, and Low-level Factors all Affect Fixation Time
Keith Rayner, Department of Psychology, University of Massachusetts, USA

 

Tuesday 9 April 2002, 16:30 - 18:30,
Paper Sessions 1, 2, 3

Session 1: Contiguity and Structure in Learning

Beyond spatio-temporal contiguity: Natural and learned audio-visual pairings use different neural integration sites
Gilles Pourtois and Beatrice de Gelder, Tilburg University, The Netherlands and Université de Louvain, Belgium

Hierarchical coding of serially ordered spatial information: Evidence from analyses of time to generate the next step in the sequence
Carlo De Lillo, University of Leicester, UK

High-order information reprocessing during post-training paradoxical sleep
Philippe Peigneux, Steven Laureys, Axel Cleeremans and Pierre Maquet, Cyclotron Research Center, Université de Liège, Belgium, Cognitive Science Research Unit, Université Libre de Bruxelles, Belgium

Session 2: Word and Text Comprehension

Comprehension complexity and corpus frequencies in noun phrase conjunction
Timothy Desmet and Edward Gibson, Department of Experimental Psychology, Ghent University, Belgium and Brain and Cognitive Sciences, Massachusetts Institute of Technology, USA

Cognitive aging effects on integration processes during text comprehension
Laurence Demanet, Marie-Anne Schelstraete, Michel Hupet and Guy Denhière, Unit Cognition and Development, U.C.L., Belgium and C.N.R.S. Université d'Aix-Marseille, France

Deficits in regular past tense processing: Delayed activation of semantic representations
Catherine E. Longworth, William D. Marslen-Wilson and Lorraine K Tyler, Centre for Speech and Language, Department of Experimental Psychology, University ofCambridge, UK and MRC Cognition and Brain Sciences Unit, Cambridge, UK

Effects of ambiguity: Further evidence from semantic categorization
Jennifer Rodd, Centre for Speech and Language, Department of Experimental Psychology, University of Cambridge

Session 3: Visual Attention and Awareness

Irrelevant attention shifts produce a Simon effect
Wim Notebaert and Eric Soetens, Vrije Universiteit Brussel, Belgium

Illusory perceptions of space and time preserve cross-saccadic perceptual continuity
Kielan Yarrow, Patrick Haggard, Ron Heal, Peter Brown and John C Rothwell, Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, UK

Visible persistence, informational persistence, and visual short-term memory in change detection tasks
Filip Germeys and Caroline Van Eccelpoel, Laboratory of Experimental Psychology, University of Leuven, Belgium

Probing the prerequisites of experimental 'blindness'
Michael Niedeggen, Guido Hesselmann, Arash Sahraie and Maarten Milders, Experimental Psychology II, Duesseldorf, Germany and Department of Psychology, Aberdeen, UK

Business Meeting, EPS

19.00 Reception

 

Wednesday 10 April 2002, 9:00 - 11:00

Symposium 5 - Age of Acquisition and Written Language Processing: the Influence of Language and Orthography
Convenor: Ilhan Raman, Middlesex University, UK

Effects of age of acquisition in semantic categorisation tasks
Marc Brysbaert, Mandy Ghyselinck and Gert Storms, Royal Holloway, University of London, UK, Universiteit Gent, Belgium and Katholieke Universiteit Leuven, Belgium

Effects of age of acquisition and word frequency on object naming, word naming and lexical decision in Spanish and English
Andrew W Ellis, Cristina Izura and Fernando Cuetos, University of York, UK and University of Oviedo, Spain

On the AoA effects and Orthographic Transparency: Evidence from Turkish
Ilhan Raman, Middlesex University, UK

Age of acquisition effects on spelling in surface dysgraphia
Brendan Weekes, Robert Davies, Ben Parris and Gail Robinson, University of Sussex, UK and National Hospital for Neurology and Neurosurgery, UK

Wednesday 10 April 2002, 9:00 - 12:30

Invited Symposium - Interaction of Implicit and Explicit Learning
Convened by Eric Soetens, Vrije Universiteit Brussel, Belgium

How to survive without the implicit/explicit distinction
David Shanks, University College, London, UK

Verbal report of incidentally experienced environmental regularity: The route from implicit learning to verbal expression of what has been learned
Peter Frensch, Humbold University, Berlin, Germany

The interaction of implicit and explicit sequence learning
Daniel B. Willingham, University of Virginia, USA

Wednesday 10 April 2002 14:30 - 16:30, Sessions 4, 5, 6

Session 4: Reading Faces

The "who said what" paradigm revisited: Insights from multidimensional scaling
Christophe Labiouse, University of Liege, Belgium and Belgian NFSR Research Fellow

Putting names to faces: No theory seems to work.
Mike Burton, Rob Jenkins and Allan McNeill, University of Glasgow, UK

Reading the mind from eye gaze
Andrew J Calder, Andrew D Lawrence, Jill Keane, Sophie Scott, Adrian M. Owen, Ingrid Christoffels and Andrew W Young, MRC Cognition and Brain Sciences Unit, University of Cambridge, UK, University College London, UK, University of Amsterdam, The Netherlands and University of York, UK

The mentalistic significance of the mouth: A comparison of deaf and hearing children's use of mouth and eye information in schematic face reading.
L Jackson, R Campbell and H Ellis, University of Reading, UK, Human Communications Science, University College London, UK and Cardiff University, UK

Session 5: Thinking and Reasoning

Does everyone "take-the-best"? Empirical tests of a 'fast and frugal' decision heuristic.
Ben R Newell, David R Shanks and Nicola J Weston, University College London, UK

Insensitivity to prior causal knowledge in inference
F J López, A Caño, P L Cobos, J Almaraz and D R Shanks, University of Málaga, Spain and University College London, UK)

Utilising threat: Anticipated regret in deontic reasoning
Nick Perham and Mike Oaksford, Cardiff University, UK

Dissociating memory processes underlying misinformation effects in young children.
Robyn Holliday, University of Kent at Canterbury, UK

Session 6: Tracing Processing through Fixations and Saccades

Fixation positions on words in English sentences.
Sarah J White and Simon P Liversedge, University of Durham, UK

Searching for information: Eye movements while attempting to verify statements about pictorial scenes
Geoffrey Underwood, Lorraine Bell and Kate Roberts, University of Nottingham, UK

Bottom-up and top-down control in visual search
Wieske van Zoest and Mieke Donk, Vrije Universiteit Amsterdam, The Netherlands

Saccadic responses indicate parallel set activation during task-switching
Charlotte Golding, Tim Hodgson and Chris Kennard, Imperial College, London, UK

Wednesday 10 April 2002 17:00 - 18:30, Sessions 7, 8, 9

Session 7: Modeling Semantic Structure

Verbal fluency from common and ad hoc categories: evidence from dementia
Arlene J Astell and Romola S Bucks, University of St. Andrews, UK and University of Southampton, UK

Conceptual structure in the normal system: Domain differences in the time course of activation of correlated and non-correlated semantic information.
Billi Randall, Helen Moss and Lorraine K Tyler, Centre for Speech and Language, Department of Experimental Psychology, University of Cambridge, UK

On the use of scaling and clustering in the study of semantic disruptions in patients with Alzheimer's disease
Gert Storms, Trinette Dirikx, Jos Saerens, Sonja Verstraeten and Peter P De Deyn, Department of Psychology, University of Leuven, Belgium, Memory Clinic, General Hospital Middelheim, Antwerp, Belgium and Laboratory of Neurochemistry and Behavior, Born Bunge Foundation, University of Antwerp, Belgium

Session 8: Phonology in Speech and Reading

In pursuit of the Syllabary: this Snark is a Boojum!
Stephen Monsell, Arie van der Lugt and Patricia Jessiman, University of Exeter, UK

The role of the rime. A cross-linguistic comparison of rime effects in reading English and Dutch
Dominiek Sandra, James Booth, Heike Martensen, Astrid Geudens and Charles Perfetti, University of Antwerp, Centre for Psycholinguistics, Belgium, Northwestern University, USA and University of Pittsburgh, USA

Lexical Bias in Spoonerisms: a 'related beply' to Baars, Motley, and MacKay (1975)
Robert J Hartsuiker, Martin Corley and Heike Martensen, University of Edinburgh, UK and University of Antwerp, Belgium

Session 9: Object Discrimination

Context-dependent asymmetries in stimulus comparisons by monkeys
Hans Op de Beeck, Johan Wagemans and Rufin Vogels, Laboratory of Neuro- en Psychofysiology, University of Leuven, Belgium and Laboratory of Experimental Psychology, University of Leuven, Belgium

Advantage of low visual acuity of the retina in 2-month-olds infants: a statistical categorization model
Martial Mermillod, Robert M French, Paul C Quinn and Denis Mareschal, University of Liège, Belgium, Washington & Jefferson College, USA and Birkbeck College, UK

Interactions between view changes and shape changes in picture-picture matching
Rebecca Lawson, Heinrich H Bülthoff and Sarah Dumbell, University of Liverpool, UK and Max Planck Institut, Tübingen, Germany

Wednesday April 10, 2002, 18:30 - 19:30

9th EPS Prize Lecture

The Role of the Prefrontal Cortex in Actions and Habits
Simon Killcross,
Cardiff University, United Kingdom

20.00 - Conference Dinner

 

Thursday 11 April 2002, 9:00 - 11:00

Symposium 6 - Memory and Attention in Timing
Convenor: John Wearden, Manchester University, UK

Operating the timing system: from automatic to controlled processes
John Wearden, Manchester University, UK

From behavioural data to underlying temporal processes: methodological considerations
André Ferrara, University of Liège, Belgium

Temporal interval production and short-term memory
David T Field and John A Groeger, University of Surrey, UK

'Shooting stars': a review and development of the multiplicative transform K* in explanations of temporal reference memory in SET
Luke Jones, University of Manchester, UK

The effect of knowledge of results on time estimation: Is there mediation by the reference memory?
André Vandierendonck and Vicky Franssen, Ghent University , Belgium

Thursday 11 April 2002, 9:00 - 10:00, Sessions 10, 11

Session 10: Codes in Memory

Semantic coding in the recall of picture and word lists shown at RSVP and STM rates
Veronika Coltheart, Stephen Mondy and Robyn Langdon, Macquarie University, Sydney, Australia

Interactions between long- and short-term phonological memory: Evidence from an implicit phonological learning paradigm
Steve Majerus, Martial Van der Linden, Thierry Meulemans and Ludivine Mulder, Research Fellow-FNRS, Neuropsychology Unit, University of Liège, Belgium, Cognitive Psychopathology Unit, University of Geneva, Switzerland and Neuropsychology Unit University of Liège, Belgium

Session 11: Shape, Space, and Language

The cultural relativity of shape categories: Goodness had nothing to do with it.
Debi Roberson, Jules Davidoff and Laura Shapiro, University of Essex, UK and Goldsmiths College, University of London, UK

Spatial discourse: Processing, memorizing, and using navigational instructions
Michel Denis, Groupe Cognition Humaine, LIMSI-CNRS, Université de Paris-Sud, Orsay, France

Thursday 11 April 2002, 10:00 - 12:30

Invited Symposium - The Relationship Between the Lexical and Semantic Systems in Word Processing
Convened by Marc Brysbaert, Royal Holloway, University of London, UK

Meaningful models of word recognition
Lorraine K. Tyler, University of Cambridge, UK

The relationship between the lexical and semantic systems in word and object processing
Max Coltheart, Macquarie University, Australia

Thursday 11 April 2002, 13:30 - 15:30

Symposium 7 - Category-specificity in Mind and Brain
Convenor: Glyn W Humphreys, Univerisity of Birmingham, UK

Domain Differences in Semantic Dementia: Implications for Theories of Category-Specific Deficits
Timothy T Rogers, Matthew A Lambon-Ralph, David C Plaut, John R Hodges and Karalyn Patterson, (MRC- Cognition and Brain Sciences Unit, Cambridge, UK)
A case of impaired conceptual knowledge for fruit and vegetables
Dana Samson and Agnesa Pillon, (Université Catholique de Louvain, Belgium)

Semantic category dissociation in Alzheimer's disease : a longitudinal study.
V Cornil and A Pillon, (Université Catholique de Louvain, Belgium)

The diversity of category-specific deficits for living things.
Glyn W Humphreys, (Behavioural Brain Sciences, School of Psychology, University of Birmingham, UK)

Category-specific representations for numbers and animals, commonly activated in twodifferent semantic tasks
Marc Thioux, Xavier Seron and Mauro Pesenti, (Université Catholique de Louvain, Belgium)

Thursday 11 April 2002 13:30 - 15:30

Symposium 8 - The Perception of Biological Motion
Convenors: Karl Verfaillie and Jan Vanrie, Laboratory of Experimental Psychology, University of Leuven, Belgium

Recognising the Style of Human Movement
Frank E Pollick, University of Glasgow, UK

Is biological motion perception modular?
Winand H Dittrich, University of Hertfordshire, UK

Interfering with biological motion
Ian M Thornton, Max Planck Institute for Biological Cybernetics, Tübingen, Germany

The role of limb movements in the perception of orientation of meaningless point-lightactions
Jan Vanrie and Karl Verfaillie, Laboratory of Experimental Psychology, K.U. Leuven, Belgium

Thursday 11 April 2002, 15:30 - 16:30, Sessions 12, 13

Session 12: Social Attitudes & Beliefs

A recurrent connectionist model of attitude formation
Frank Van Overwalle, Vrije Universiteit Brussel, Belgium

Openness to Experience and Boundaries in the mind
Alain Van Hiel and Ivan Mervielde, Ghent University, Belgium

Session 13: Development of Concepts & Percepts

Cognitive factors and concept learning: A developmental approach.
Sabine Gelaes and Jean-Pierre Thibaut, Université de Liège, Belgium

Perception of partial collision events in infancy
Peter Dejonckheere, Ad Smitsman and Leni Verhofstadt-Denève, Ghent University, Belgium and University of Nijmegen, The Netherlands

Thursday 11 April 2002, 13:30 - 16:30, Session 14

Session 14: Strategy, Working Memory Capacity, and Inhibitory Control

What makes an insight problem? An investigation into the role of strategy-goal congruency.
Edward P Chronicle, James N MacGregor and Thomas C Ormerod, Lancaster University, UK and School of Public Administration, University of Victoria, Canada

Strategy use in relation to mathematical ability: Developmental delay or deficit?
Joke Torbeyns, Lieven Verschaffel and Pol Ghesquière, K.U. Leuven Research Assistant FWO - Vlaanderen, Belgium and K.U. Leuven, Belgium

The role of working memory in the carry operation of mental arithmetic
Stijn De Rammelaere and Ineke Imbo, Department of Experimental Psychology, Ghent University, Belgium

Working memory capacity in causal reasoning: blocking background knowledge
Wim De Neys, Walter Schaeken, and Géry d'Ydewalle, KU Leuven, Belgium

How to know what to inhibit: Action-effects are used in response-suppression
Bernie Caessens, Karen Mortier and André Vandierendonck, Department of Experimental Psychology, Ghent University, Belgium and Cognitive Psychology Section, Vrije Universiteit Amsterdam, The Netherlands

Aging effects in inhibitory control over no-longer relevant information during a garden-path sentence task
Valentine Charlot and Pierre Feyereisen, Unit Cognition and Development, UCL, Belgium

 

ABSTRACTS AND POSTERS

 

Tuesday 9 April 2002, 9:30 - 11:30,

Symposium 1 - Spoken Word Recognition
Convenors
James McQueen and Anne Cutler, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
Alain Content, Free University Brussels, Belgium

Perceptual assimilation and lexical access.
Uli H. Frauenfelder1, Pierre Hallé2, and Juan Segui2
1. University of Geneva, Switzerland
2. CNRS, University of Paris V, France
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Our previous work has shown that /dl/ and /tl/, illegal word-initially, are perceptually assimilated to /gl/ and /kl/, respectively. We investigated the effect of this phenomenonon word recognition. Nonwords derived from /gl, kl/ base words by a velar-to-dental change (e.g., dlaïeul derived from "glaïeul") were generally perceived as words. These nonwords, used as primes in a cross-modal form-priming task, produced almost as much priming as did the base words. Legal nonwords such as droseille, derived from words by this same change produced much less priming. Such differential effects on word recognition suggest that the goodness of fit determining lexical activation depends not solely upon the phonetic features shared by the input and lexical forms, but also upon possible perceptual assimilation. The findings are a challenge for models proposing direct lexical access from phonetic features and support the existence of intermediary stages of perceptual integration into sublexical units.

Is the syllable an intermediate representation in French speech processing? Evidence from form priming in nonwords.
Nicolas Dumay
University of York, United Kingdom
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The nature of the representations mediating access to the auditory input lexicon in French was investigated using intramodal phonological priming. More specifically, we examined to what extent final overlap facilitation relies on syllable overlap, by varying orthogonally the amount of shared acoustic-phonetic information and the syllabic correspondence between nonwords. Targets of CVC.CVC structure (goltibe) were preceded by primes with a syllabic overlap of three phonemes (.CVC; purtibe) or a supra-syllabic overlap of four phonemes (C.CVC; pultibe). Conversely, CV.CCVC targets(pinclude) were preceded by primes with a syllabic overlap of four phonemes (.CCVC; viclude) or an infra-syllabic overlap of three phonemes (._CVC; viflude). Two target-shadowing experiments were performed, with Experiment 2 including foils (e.g.modrugue-padrouve). Foils had no influence on RT results. Overall, the pattern of shadowing latencies indicated that final overlap facilitation is primarily determined bythe amount of acoustic-phonetic overlap, with smaller (but reliable) priming effects for the three-phoneme overlap conditions (including the infrasyllabic one) than for the four-phoneme conditions. Priming was also found on error rates which were equally less numerous in the related conditions than in controls, with again no influence of the syllabic structure. Implications of these data for theories of pre-lexical processing in spoken word recognition will be discussed.

French speakers' syllabification of trisyllabic pseudowords.
Alain Content
Free University Brussels, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Previous investigations of French speakers' intuitions about syllabification have shown striking asymmetries between syllable onsets and offsets in disyllabic words. Decisions about onsets were found to be highly consistent. In contrast, syllable endings decisions showed a large variability and were influenced by consonant sonority and spelling(Content, Kearns & Frauenfelder, 2001). This asymmetry led us to propose the SOSHhypothesis, according to which syllable onsets constitute privileged segmentation and alignment points for lexical mapping. In this talk, I will present a new set of syllabification data using trisyllabic pseudowords, which confirms the previous findings and allows us to eliminate alternative/artefactual explanations of the onset/offset asymmetry.

Content, A., Kearns, R.K. & Frauenfelder, U.H. (2001). Boundaries versus onsets in syllabic segmentation.Journal of Memory and Language, 45, 177-199.

Lexical activation in spoken-word recognition: Insight from the pause-detection paradigm.
Sven Mattys
University of Bristol, United Kingdom
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

This study explores the sensitivity of a new paradigm--Pause Detection (PD)--to lexical activity during speech processing. In PD experiments, listeners speed-detect 150-mspauses [p] artificially inserted in speech sequences. Pauses inserted in multisyllabic spoken sequences were detected more slowly after words (e.g., camper[p]ton.dee.lo) than after nonwords (e.g., goomper[p]ton.dee.lo), but the effect gradually decreased with longer stimuli. Lexical inhibition was also found to depend on the uniqueness point of the stimuli: Late-unique stimuli caused pause detection to be delayed. Finally, pauses were detected more slowly after high-activity than low-activity nonwords (based on the size o ftheir initial cohort). It is argued that PD latencies can be used as an on-line gauge of lexical activity during speech processing. PD also offers a number of features that complement those of existing paradigms: (a) it reflects the total amount of activity in the lexicon as opposed to that of hand-picked tokens, i.e., it is a better analogy for global activity in computational modeling, (b) because the task is acoustic in nature, linguistic effects might provide an insight into the automaticity and modularity of speech processing, and (c) PD protocols can easily be transferred from speech to non-speech and from one language to another.

Lexical re-tuning of phonetic categories during speech perception.
Dennis Norris1, Anne Cutler2 and James M. McQueen2
1. MRC Cognition and Brain Sciences Unit, Cambridge, United Kingdom
2. Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A series of experiments show that listeners use lexical knowledge in learning how to interpret ambiguous speech sounds. Dutch listeners were asked to make lexical decisions to a list of spoken Dutch words and nonwords. In some words, the final fricative had been replaced by an ambiguous sound, midway between [f] and [s]. One group of listeners heard ambiguous [f]-final words like [kara?] (based on karaf, carafe) and unambiguous [s]-final words (e.g., karkas, carcase). Another group heard the reverse(ambiguous [karka?], unambiguous karaf). Since neither [karas] nor [karkaf] are Dutch words, lexical information indicated how the final fricatives ought to have been interpreted. After the lexical decision phase, listeners categorised a range of ambiguous[f]-[s] sounds. Those who had heard [?] in [f]-final words were more likely to categorise the ambiguous fricatives as [f] than the listeners who had heard [?] in [s]-final words. Control conditions showed that this effect requires exposure to [?] in lexical contexts in the lexical decision phase. These findings demonstrate that lexical information can b eused to train categorisation of the speech signal. This use of lexical information is qualitatively different from the feedback built into interactive models of speech perception. 

Tuesday 9 April 2002, 9:30 - 13:00

Invited Symposium

Visual Perception of Objects, Scenes, and Actions: Commonalities and Distinctions
Convened by Peter De Graef and Karl Verfaillie
University of Leuven, Belgium

Diagnostic recognition: A new informational framework for object categorization
Philippe Schyns
University of Glasgow, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Nowadays, discoveries about the formation of face, object or scene categories, the attention to information in different recognition tasks, and the mechanisms of recognition do not really inform research on the processes of low-level vision. Conversely, models of face, object and scene recognition and categorization are not always firmly grounded on the established principles of early vision. Higher-level cognition and perception are simply drifting apart.

Using examples from face, object and scene recognition, I will present new methods and results that bridge the gap between object categorization, the selective attention to diagnostic information, and the perception of the stimulus. I will propose a new framework based on the selective use of diagnostic information to ground categorization firmly into perception.

The understanding of goal-directed actions: functional neuroanatomy
Julie Grèzes
Wellcome Department of Neurology, London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Our ability to generate and to recognise the actions performed by others is the bedrock of our social life. Neuroimaging techniques (PET and fMRI) have been used to specifically explore, inhuman, the nature of the links between perception and action, subserving the understanding of goal-directed actions. By 'understanding goal-directed action', we imply the mechanisms b which the subject understand and generate the action that is appropriate for an object (through its visual perception), but also the mechanisms by which the subject reads goal-directed actions performed by others (through their visual perception).

Our results demonstrated that observation is a selective process that recruits specific neural networks depending both on the nature of the stimuli perceived and on the subject's purpose during the observation phase. They however also suggest that the perception of manipulable objects and of other's actions share some common neural mechanisms (subserve by the parietal and premotor cortex) with action generation, therefore providing neurophysiological evidence to a link between perception and action.

fMRI investigations of high-level vision in humans: people, places, and things
Nancy Kanwisher
Department of Brain and Cognitive Sciences at MIT, USA
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Work in my lab over the last 5 years has used fMRI to identify and characterize three regions of human extrastriate cortex that respond selectively to specific stimulus classes: the fusiform face area (FFA) for faces, the parahippocampal place area (PPA) for places, and the extra striate body area (EBA) for bodies. Another region of cortex called the lateral occipital cortex (LOC)apparently represents object shape in a category-independent fashion. I will review these findings, and then describe ongoing work in our lab that pursues a number of questions that arise from this work, such as: 1) What is the nature of the representations that are extracted in each of these areas?, 2) Does each category-selective region of cortex primarily provide information about the category it responds selectively to, or does it also provide information about "nonpreferred" stimuli?, 3) How does activity in each of these areas relate to behavioral performance? and 4) Does extrastriate cortex contain other category-specific cortical regions?

 

Tuesday 9 April 2002, 14:00 - 16:00

Symposium 2 - Prospective Memory
Convenor Géry d'Ydewalle, University of Leuven, Belgium

A prospective study of prospective memory: Challenges due to procedural changes for an fMRI study
Wim De Bruycker, Géry d'Ydewalle, & Els Brunfaut
University of Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Prospective memory (PM) is memory for activities to be performed in the future. In order to carry out a fMRI study on PM, the standard PM task is to be modified in two important ways: The PM task is to be divided into separate blocks of 1 min duration, alternated with blocks with background task only; and the time interval between consecutive PM cues/critical moments is to be shortened to 30 s. Two experiments explored the importance of these procedural changes. In Experiment 1, performance in time-based and event-based PM blocks of different durations (1 vs. 4 min) was compared. Typicality and perceptual distinctiveness of the cues in event-based PM blocks were also manipulated. Experiment 2manipulated the time interval between consecutive cues in an event-based and a time-based PM task (30, 60, or 120 s). Discussion will focus on whether the procedural changes reduce PM tasks to simple vigilance and time-monitoring tasks.

Activation of performed and to-be-performed activities in healthy and impaired older adults
J. E. Freeman & J. A. Ellis
University of Reading, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Activities intended for enactment are more accessible in young adults than activities that are not to be enacted (Goschke & Kuhl, 1993). We investigated this intended enactment effect in healthy older adults and in individuals with low MMSE scores indicative of possible dementia. In a laboratory-based task, using recognition latencies as a measure of item activation, young and healthy older adults showed an equivalent advantage for to-be-performed activities over verbally encoded items not intended for enactment. These two groups also showed a benefit of overtly performing actions during encoding, highlighting possible links between subject-performed task (SPT) and intended enactment effects. Both of these effects were absent in the low MMSE group. Examining naturally-occurring intentions, both healthy and low scoring MMSE older adults showed impaired activation for everyday intentions as compared with young adults (cf. Maylor et al., 2000). The role of motoric information in the intended enactment effect and implications for understanding age-related declines in prospective remembering will be discussed.

Event-based prospective memory in 3- to 9-year old children: The effects of age,explanation and type of action
L. Kvavilashvili1, D. J. Messer2, and F. E. Kyle3
1. University of Hertfordshire, UK
2. South Bank University, UK
3. Royal Holloway, University of London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In most of the studies on event-based prospective memory (PM) participants have to remember to insert an additional action into their on-going activity whenever they see a target event (e.g., press a key when seeing a word 'chair' while rating words for pleasantness). However, in everyday life, prospective remembering may often involve the substitution of one action for another or the inhibition of a habitual response (Ellis,1996). In the present study, 3-, 5-, 7-, and 9-year old children (N=480) were naming the pictures as part of the game and had to either say something additional when they named a picture of a dog (insertion condition), say something else instead of a dog (substitution condition) or not say anything (inhibition condition). Half of the children received a plausible explanation as to why they had to carry out this task and the other half did not. The results revealed a clear age effect in PM performance with older children performing better than younger children but this effect explained only 2% of variability when 3-yearolds were excluded from the analyses. There was also a main effect of explanation so that performance was significantly better in explanation than in no explanation condition especially in 5-, 7-, and 9-year olds. Finally, the PM performance was worst in the inhibition condition and the highest in the substitution condition. The methodological, theoretical and practical implications of these findings will be discussed.

Complex prospective memory development in children
M. Martin1, M. Kliegel1, and J.A. Ellis2
1. University of Heidelberg, Germany
2. University of Reading, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Despite its importance for the cognitive development and the everyday life of children, little is known about the developmental course of prospective memory in preschool and elementary school age. In this study with 115 children between 6 and 11 years, we used a computer-based procedure to measure age-related differences in prospective memory performance. In addition, we examined the predictive power of retrospective memory and planning performance on prospective memory performance. The results suggest an age-related increase of prospective memory performance from preschool age to the end of the elementary school years. In addition, prospective memory performance was related to retrospective memory and planning performance. The findings are discussed with respect to future studies of memory processes relevant in the everyday life of children.

Tuesday 9 April 2002, 14:00 - 16:00,

Symposium 3 Evaluative Conditioning
Convenors
Andy Field
University of Sussex, UK
Jan de Houwer
University of Ghent, Belgium

Visual Evaluative Conditioning and Contingency Awareness: Past Controversies and Current Wisdom
Andy Field
COGS, University of Sussex, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The controversial claim that evaluative conditioning (EC) can occur without contingency awareness has set EC apart as a distinct form of associative learning (Baeyens et al.,1990). However, the claim remains controversial (see Shanks & Lovibond, 2002; Fulcher & Hammerl, 2001; Field, 2001; Field 2000). This talk reviews this controversy before discussing some recent developments that may help us understand the wealth of conflicting evidence for learning without contingency awareness.

Three experiments are described that systematically investigate the role of contingency awareness in evaluative conditioning (EC) in a picture-picture paradigm in which conditioned stimuli (CSs) and unconditioned stimuli (UCSs) were counterbalanced across subjects to overcome previously discovered experimental artifacts (e.g. Field &Davey, 1999). Conditioned responses for individuals who had contingency awareness enhanced were compared against a control group and groups for whom awareness was impeded using verbal instruction, a distracter task, or backward masked UCS presentations. EC effects were obtained in aware individuals compared to control participants, but for unaware participants effects depended on the use of a distracter task. The results of the three experiments along with a structural equation model of conditioning effects across all of the data indicates that (1) associative EC effects can be obtained without contingency awareness; and (2) distraction has in independent effect on conditioning. These results shed some light onto the possible boundary conditions that could explain past inconsistencies in obtaining conditioning effects in the visual paradigm.

Evaluative learning that results from an aversive conditioning procedure: an overview
Dirk Hermans, Geert Francken, and Debora Vansteenwegen
University of Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The tradition of evaluative learning has mainly developed as a rather separate research domain within the field of learning psychology. Most evaluative conditioning studies have employed paradigms that were specifically developed to study the process of acquired evaluative change (e.g. picture-picture paradigm, taste-conditioning paradigm).One of the typical characteristics of these paradigms is that they are essentially all higher-order conditioning paradigms. The unconditioned stimuli (US) that are used in these studies (e.g. a bad taste, a picture of a gun, a pleasant odour) are not 'unconditionally' positive or negative, but have acquired their valence through previous learning experiences.

More recently, however, a series of studies aimed at investigating evaluative learning in the context of an aversive conditioning preparation, in which an electrocutaneous stimulus was employed as US (e.g. Francken et al., 2001; Hermans et al., in press a, b, c; Vansteenwegen et al., 1998; see also work by Lipp, Hamm, Öhman). This line of research has not only demonstrated that evaluative learning can be observed in aprototypical expectancy/preparatory conditioning preparation, but is interesting in at least three respects. First, these studies corroborate previous conclusions concerning the functional characteristics of evaluative learning. Second, because several of these studies have employed alternative measures of stimulus valence (e.g. startle response; affective priming), they provide interesting insights in these measures. Third, because of the particular nature of the aversive conditioning procedure, these studies also provide insight in the possible role of acquired stimulus valence in the treatment of anxiety disorders and possible associated return of fear.

Associative transfer of non-evaluative stimulus properties
Jan De Houwer1, Tom Meersmans2, Frank Baeyens2, & Paul Eelen2
1. University of Ghent, Belgium
2. University of Leuven, Belgium
E-mail: Jan.De This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Evaluative conditioning refers to the transfer of stimulus valence from a US to a CS with which the US was repeatedly paired. We examined whether other, non-evaluative stimulus properties of the US can also transfer to the CS. In a series of studies, we failed to find conditioning of judgements of the brightness of pictures, the semantic category of words, the product category associated with drinks, the carbonation level of drinks, and he age of persons.

The allocation of attention to stimuli imbued with valence through evaluative learning
Eamon Fulcher
Department of Psychology, University College Worcester, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Previous research has shown that individuals scoring highly on measures of anxiety or negative emotionality, selectively attend to threat-related material. One consequence of this attentional bias may be to increase the perception of potential threats in the environment. In an attempt to understand the origins and nature of attentional bias, we tested the possibility that this bias can be extended to newly acquired unpleasant material, via evaluative learning. We first paired novel pictures with words that cued either pleasant or unpleasant personal experiences, and then tested liking for these pictures, before proceeding to test the effects of this learning on attentional interference .Our results show that participants with high neuroticism scores were more distracted by the pictures paired with unpleasant cues than were those with low neuroticism scores. We therefore conclude that attentional bias effects that differ across high versus low neuroticism groups can be produced by new evaluative learning. Our results suggest that there might be a cyclic interaction between attentional bias and evaluation, such that a stimulus with an acquired negative evaluation tends to capture attentional resources more readily in high negative emotion-prone individuals; and that such attentional capturere inforces the acquisition of negative evaluation. An interesting finding is the lack of a consistent association between evaluative learning and accuracy of episodic memory, and this supports the assumption that these latter outcomes reflect the operation of two independent systems. This provides a plausible explanation for the apparent paradox that vulnerable individuals can be distracted by emotional cues without being able to report on the origins of these effects.

Tuesday 9 April 2002, 14:00 - 16:00,

Symposium 4 - Eye Movements and Visual Cognition
Convenor
John Findlay
University of Durham, UK

Executive contributions to eye movement control
Timothy L Hodgson
Imperial College of Science, Technology and Medicine, Charing Cross Hospital Campus, London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

This paper addresses the question of how humans perform in situations where task rules change dynamically from moment to moment. Using several tasks which involve the control eye movements based on changing task rules, we show that neurologically normal individuals experience an influence of earlier rules on the spatial and tempora properties of saccades. In most situations normals are able overcome this tendency in order to control behaviour based on the new rule. However, in situations where there are no external cues to indicate the correct task, patients with frontal lobe damage continue to make responses based on old rules. In contrast, when the correct rule is directly instructed, patient performance is found to be similar to controls. Rather than a deficit in top-down control, this pattern is more consistent with a deficit in the self-regulatory functions required to over-ride reinforced behaviour. We propose that frontal cerebral cortex monitors conflict between actual and optimum neural states and adaptively biases competitive neural interactions to meet high-level goals. In this way, our brains are able to implement the flexible control of behaviour required to meet the challenge of our ever-changing environment.

Exogenous and endogenous saccades: Effect of dual-task interference from an actionrepresentation based view
Els Stuyven
Department of Experimental Psychology, Ghent University, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In order to solve the binding problem in action planning, the action-concept model ofHommel assumes that the execution of an intentional task needs the construction of anaction-concept (action plan), an integrated representation (binding) of stimulus, responseand effect codes. When an action plan requires a code already integrated in anotheraction-concept, performance is impaired because this code is temporarily less available.In our research, we used this idea in a study on saccadic eye movements. Using anABBA design, participants were asked to plan a manual binary choice task, but postponeits execution until after the generation of a saccadic eye movement, on whichcompatibility effects were studied. In line with our hypothesis, overlap costs wereobserved only with endogenous, but not with exogenous saccades. However, it appearedthat endogenous saccades triggered by a inherently spatial stimulus (an arrow), alsolacked binding effects. These results were replicated with hand and foot responsescombined, showing that the role of the spatial characteristics of stimuli in these overlapcosts is more general. Further experiments, however, suggest that not the inherentlyspatial nature of the stimulus plays a role, but that the "endogenous" character of acompatible response on an arrow stimulus should be doubted.

Does scene context and fixation position affect the processing of objects in scenes?
Lynn Gareze and John. M. Findlay
Department of Psychology, University of Durham, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

We examine whether scene context affects the visual recognition of objects presentwithin them. Past research reporting inconsistent object "pop out" has been criticised fornot being replicable and having serious material and design flaws. However,Hollingworth and Henderson (2000) found new evidence for an inconsistent objectadvantage in a change blindness task. We report four experiments which further examinethe issue, employing a forced choice recognition test following a brief presentation withfixation position controlled.

In Experiment 1, line drawings of both consistent and inconsistent objects in scenes wereused. Performance for consistent objects decreased faster than that for inconsistentobjects as distance from fixation increased and the difference was marginally significant.This suggests that inconsistent objects were more reliably detected in extrafoveal vision.To investigate the applicability of these findings to natural scenes, the same procedurewas carried out using photographs of real-life scenes (Experiment 2). The resultsindicated no difference between the recognition of consistent and inconsistent objects.

To determine whether this discrepancy could be explained by the nature of the material,line drawings were created matching the photographs used in Experiment 2. Experiment3 used the same procedure as the earlier ones and experiment 4 presented the original linedrawings (from Experiment 1) shown upside down, to inhibit the processing of the sceneas a semantic whole. In neither experiment was any advantage for inconsistent objectsobtained. We conclude that demonstrations of 'inconsistent object advantage' are veryfragile.

Hollingworth, A. and Henderson, J. M. (2000) Semantic informativeness mediates the detection of changesin natural scenes. Visual Cognition, 7, 213-235.

The visual analog in transsaccadic object perception
Peter De Graef and Karl Verfaillie
Laboratory of Experimental Psychology, University of Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Numerous studies have investigated whether object information acquired on a givenfixation is stored across saccades and integrated with object information from subsequentfixations. In other words, what are the contents of transsaccadic object memory? Studiesusing saccade-contingent and/or transient-masking techniques to camouflage objectchanges have recently suggested that transsaccadic object memory may be subserved bya visual analog. Specifically, the sparse and abstract object representation which is foundto survive saccades may be the result of selective attentional processing of object featuresin a maskable, non-selective and spontaneously decaying scene snapshot taken during thepresaccadic fixation. To examine this hypothesis, we had viewers saccade to an object ina scene, and intrasaccadically changed the display to a blank field with alocation cue.Subsequently, the blank + cue display was replaced by a scene in which the object at thecued location had changed its in-depth orientation. Viewers were asked to identify thedirection of the orientation change. We manipulated the spatial correspondencebetweenthe cue and the target of the preceding saccade, the onset delay of the cue, andthe duration of the blanking period. In this manner, we attempted to determine to whatextent a single fixation automatically yields a high-capacity and detailed visual analogfrom which an attention-based transfer produces the selective and abstract transsaccadicobject representation observed in studies of transsaccadic integration and changedetection.

Eye Movements in Reading: Word Frequency, Word Predictability, and Low-levelFactors all Affect Fixation Time
Keith Rayner
Department of Psychology, University of Massachusetts, USA
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In this talk, I will first describe the results of an experiment in which word frequency andword predictability varied for a target word.  Basically, the results yielded effects of eachvariable and no interaction of the two variables.  Then, I will discuss evidence for an'inhibition of return' effect in reading: when readers make saccades back to a word thatthey just fixated, their fixations are longer than when the saccade is to a word that theydid not just fixate.  Together, the results indicate that both low-level factors and lexicalfactors influence fixation time.

Currently Leverhulme Visiting Professor, Department of Psychology, University of Durham, UK

 

Tuesday April 9, 2002, 16:30 - 18:30, Sessions 1, 2, 3

Session 1: Contiguity and Structure in Learning

Beyond spatio-temporal contiguity: Natural and learned audio-visual pairings use different neural integration sites
Gilles Pourtois1, 2 and Beatrice de Gelder1, 2
1 Tilburg University, The Netherlands
2
Université de Louvain, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Studies of inter-sensory integration of auditory and visual information tended to assume thattemporal and spatial contiguity is the single most important factor determining intersensoryintegration. In the present study we asked whether the specific type of audio-visual pairingalso plays a role. If so, spatio-temporal contiguity is not sufficient for integration andneuronal sites of audio-visual integration will reflect content-sensitivity. We studied whetherTranscranial Magnetic Stimulation (TMS) disrupted audio-visual integration as reflected inthe redundant target advantage. Single pulse TMS applied over the left posterior parietalcortex at 50, 100, 150 and 200 ms disrupted integration at 150 ms and later of audio-visualshape/tone pairs (Learned condition) but not of voice/face pairs (Natural condition). Ourresult indicates that besides spatial and temporal contiguity, content specificity is animportant determinant of audio-visual integration.

Hierarchical coding of serially ordered spatial information: evidence from analyses of time to generate the next step in the sequence
Carlo De Lillo
University of Leicester, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The results of two experiments are reported. In the first experiment participants were presented with a configuration of nine identical icons, spatially grouped in three clusters of three icons each, on a touch sensitive computer monitor. The icons flashed according to sequences segregated by spatial clusters and, after a short delay, the participants were required to reproduce the sequences by touching the screen. An analysis of the latencies for touches corresponding to different ordinal positions in the sequence revealed longer latencies at cluster boundaries. These results corroborate previous findings and are compatible with the hypothesis that a two-level hierarchical representation underpins the reproduction of the sequences.

The second experiment was carried out to rule out the possibility that results of experiment one could have been accounted for by the relative length of the pointing movements. As in experiment one, the participants observed first a sequence of flashing icons on the screen. Then, segments of the sequence were presented. The participants were required to produce a single pointing movement to the icon corresponding to the next ordinal step in the sequence, with their hand starting from a resting position located at a fixed distance from the screen. Longer latencies emerged again for pointing responses directed to icons at ordinal positions corresponding to cluster boundaries. Taken together, the results of these two experiments provide strong evidence for the emergence of a form of spatial chunking in tasks requiring the encoding of serially ordered information within spatially structured patterns.

High-order information reprocessing during post-training paradoxical sleep
Philippe Peigneux1, Steven Laureys1, Axel Cleeremans2, and Pierre Maquet1
1 Cyclotron Research Center, Université de Liège, Belgium
2
Cognitive Science Research Unit, Université Libre de Bruxelles, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The brain areas needed for the practice of a serial reaction time (SRT) task are more active during subsequent REM sleep in subjects trained to the task than in non trained subjects [Maquet et al. (2000) Nature Neuroscience, 3(8), 831-836]. These experience-dependent cerebral reactivations during post-training REM sleep could reflect the reprocessing of recent memory traces. Here, 6 new subjects were trained to the same SRT task then scanned during the post-training night using PET. The only difference with the trained group in the Maquet et al. study was that the sequence of stimuli was at random. Therefore, both trained groups underwent similar visuo-motor basic learning, but only one trained group learned complex, high-order, rules underlying the sequence of stimuli during SRT practice. Hence, this group only could potentially reprocess high-order information during post-training sleep. We found that post-training REM sleep activity in the thalamus, occipital and premotor cortex increased more in subjects trained to a structured sequence (with rules) than in subjects trained to the random sequence. It suggests that experience-dependent cerebral reactivations during post-training REM sleep underlie the reprocessing of high-order information about the structure of the sequential material to be learned.

Supported by FNRS, FMRE, ULg Funds

Perceptual or motor learning with artificial and fixed sequence structures
Natacha Deroost, Annemie Melis, and Eric Soetens
Vrije Universiteit Brussel, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

We investigate whether sequence learning in a serial reaction time (SRT) task is primarily perceptual or motor by varying the stimulus dimension on which the sequence structure is imposed. In a previous study, with fixed sequences, a two-choice task with symbolic S-R mapping was used. Learning only occurred in the condition where both dimensions were structured. There was no evidence for pure perceptual (location) or motor (colour) learning. In a subsequent study we replicated the experiment with an artificial grammar, using a four-choice task. To find out whether motor learning would occur, the structure was imposed on the relevant colour dimension, while location varied randomly. Unlike the first study, participants were able to learn the motor sequence. In the present study we investigated if the same results hold with a fixed sequence structure. Subjects again had to respond to colour, while ignoring the irrelevant location of the stimulus. The following three conditions were manipulated between-subjects: a repeating 32-element sequence was imposed either on the relevant colour dimension, on the irrelevant location dimension or on both stimulus dimensions. Results will be discussed in the course of the presentation.

Session 2: Word and Text Comprehension

Comprehension complexity and corpus frequencies in noun phrase conjunction
Timothy Desmet1 and Edward Gibson2
1
Department of Experimental Psychology, Ghent University, Belgium
2
Brain and Cognitive Sciences, Massachusetts Institute of Technology, USA
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A number of researchers have proposed that sentence comprehension is frequency driven, such that the ease of understanding a syntactic construction depends on its frequency of use (e.g., Mitchell, Cuetos, Corley, & Brysbaert, 1995). In apparent contradiction to such accounts, Gibson and Schütze (1999) showed that on-line disambiguation preferences do not always mirror corpus frequencies. When presented with the syntactic ambiguity involving the conjunction of a noun phrase to three possible attachment sites, participants were faster to read attachments to the first site than attachments to the second one, although the latter were shown to be more frequent in text corpora. In the present study, we investigated whether a particular feature in the items of Gibson and Schütze - disambiguation using the pronoun "one" - could account for the discrepancy they found. On the basis of an investigation of the Brown and Wall Street Journal text corpora and a self-paced word-by-word reading study, we conclude that there is no discrepancy between on-line preferences and corpus frequencies, and consequently there is no need to assume different processes underlying sentence comprehension and sentence production based on this syntactic ambiguity, as Gibson and Schütze had hypothesized.

Cognitive aging effects on integration processes during text comprehension
Laurence Demanet1, Marie-Anne Schelstraete1, Michel Hupet1, and Guy Denhière2
1 Unit Cognition and Development, U.C.L., Belgium
2
C.N.R.S. Université d'Aix-Marseille, France
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In his model of text comprehension, Kintsch (1998) postulated integration processes allowing the incorporation of new information to already known information at different levels. On the first level, some parts of the already-built text representation are selected by the leading edge strategy (L.E.S.) and maintained in a limited capacity working memory buffer (Kintsch & van Dijk, 1975). This L.E.S. allows the readers to store in the buffer the most important and the most recent propositions of the current processing cycle. On the second level, the content of the buffer is supposed to be regularly updated and integrated in the long-term working memory (Ericsson & Kintsch, 1995) to progressively build a coherent text base. Finally, on a third level, some knowledge-based information stored in the long term memory- e.g. inferences- are recovered during the reading to ensure the comprehension. Many studies showed an age-related decline in text comprehension (Van der Linden & Hupet, 1994) that could be interpreted by integration problems (Hess, 1995). The purpose of the present research was to measure how aging could affect the three different levels of integration. Three groups of participants (young, old and very old) were compared in three different tasks: A Reading-Recognition-Comprehension Task to test the L.E.S. and the comprehension, a Verbal Reconstruction Task to assess integrative function of long term working memory and finally a Reading Task of sentence pairs varying in causal relatedness to study inferential processes. Results indicated that very old participants have difficulties to draw inferences and a reduced capacity to integrate information in long-term working memory.

Deficits in regular past tense processing: Delayed activation of semantic representations
Catherine E. Longworth1, William D. Marslen-Wilson2 and Lorraine K. Tyler1
1
Centre for Speech and Language, Department of Experimental Psychology, University ofCambridge, UK
2
MRC Cognition and Brain Sciences Unit, Cambridge, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Double dissociations between the regular and irregular English past tense (Marslen-Wilson and Tyler, 1998, Tyler, de Mornay-Davies, Anokhina, Longworth, Randall and Marslen-Wilson, 2002) imply separable systems processing morphophonologically complex and fully listed words. An alternative account (Joanisse and Seidenberg, 1999) argues that these double dissociations reflect impairments of phonology or semantics, with regular past tense deficits reflecting impaired phonological and spared semantic processing. We tested whether activation of semantic representations from regular past tense forms is normal in patients with regular past tense deficits. Healthy volunteers show equal semantic facilitation from verb primes irrespective of verb regularity and tense (Longworth, et al., 2001). If non-fluent aphasics have a normal time course of semantic activation from the regular past tense they should show similar priming. 4 non-fluent patients were tested using an auditory semantic priming/lexical decision task. Prime-target pairs (e.g. "jumped LEAP") were selected by manipulating semantic relatedness, verb tense and regularity. Verb stems showed semantic priming irrespective of regularity. There was no semantic priming for the regular past tense but normal priming for the irregular past tense. This suggests that patients with regular past tense deficits have an abnormal time course of semantic activation from the regular past tense.

Effects of ambiguity: Further evidence from semantic categorization
Jennifer Rodd
Centre for Speech and Language, Department of Experimental Psychology, University of Cambridge, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Semantic ambiguity can be used as a tool to investigate how the meanings of words are represented. Rodd, Gaskell and Marslen-Wilson (in press) report slower lexical decisions for words with multiple unrelated meanings (e.g. bark) compared with unambiguous words (e.g. cage). In contrast, they report a benefit for words with multiple related word senses (e.g. twist). I present a connectionist model that simulates these apparently opposite effects, in which retrieving word meanings is characterised as activating distributed semantic representations. The ambiguity disadvantage arises because of interference between different meanings, while the sense benefit arises because of differences in the structure of the attractor basins. Words with few senses develop deep, narrow attractor basins, while words with many senses develop shallow, broad basins. The model suggests that the sense benefit arises in lexical decision because only general semantic information is retrieved. It predicts that the sense benefit should be reversed when detailed semantic information must be retrieved. This prediction is confirmed in two semantic categorisation experiments. These findings are consistent with the view that the meanings of words correspond to stable states within a high-dimensional semantic space, and that variation in the meanings of words shapes the landscape of this space.

Session 3: Visual Attention and Awareness

Irrelevant attention shifts produce a Simon effect
Wim Notebaert and Eric Soetens
Vrije Universiteit Brussel, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In a Simon task subjects have to react to a non-spatial feature (e.g., colour) of the stimulus with a left or right response. Stimuli are presented to the left or right of the fixation cross. Reaction times (RTs) are faster when the irrelevant location of the stimulus corresponds with the response location. In the present study we conducted two experiments with auditory stimuli to further support the claim that the Simon effect is caused by an attention shift towards the stimulus location. In Experiment 1, subjects have to react to the pitch of a tone that is presented in the left or right ear, with a left or right response. Two response-stimulus intervals (RSI) are used in order to manipulate the attention shifts during the task. With a short RSI, there is no Simon effect for location repetitions because no attention shift towards the stimulus location is needed In Experiment 2, subjects had to react to the colour of a centrally presented visual signal. At stimulus onset, an irrelevant tone is presented in the left or right ear. The data demonstrate a Simon effect according to the irrelevant auditory signal. This demonstrates that even an irrelevant attention shift produces a Simon effect.

Illusory perceptions of space and time preserve cross-saccadic perceptual continuity
Kielan Yarrow, Patrick Haggard, Ron Heal, Peter Brown and John C. Rothwell
Sobell Department of Motor Neuroscience & Movement Disorders, Institute of Neurology, University College London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

When glancing at a clock with a silently ticking second hand, observers sometimes perceive the first second to take longer than subsequent seconds do; time appears to be stretched following a saccade (Brown and Rothwell, 1997). A matching methodology was employed to further explore this temporal illusion (chronostasis). Subjects saccaded to a digital counter, with the resulting electro/infra-red oculogram used to trigger counter onset. The duration of the first count was varied, with subsequent counts taking one second. Subjects made a forced choice response (first count less than/greater than subsequent counts), with either a modified binary search procedure or logistic regression analysis employed to provide a single matched estimate. A control condition yielded a matched estimate in the absence of a saccade.

Experiment 1 established chronostasis' dependency upon saccade size (22º, 55º). Results suggest that a backward matching mechanism is being employed , with stimulus onset being predated to saccade onset (minus a constant). Follow up experiments indicated that chronostasis is genuinely saccade dependent. It does not disappear when preceded by active orienting of attention in the direction of the upcoming saccade, suggesting that attention is not the crucial factor (experiment 2). No chronostasis was observed when the counter moved to the point of fixation with no saccade (experiment 3). Chronostasis is critically dependent upon the brain's assumption that the saccade target (the counter) remains constant across the saccade. When one aspect of this constancy (position) is noticeably violated, chronostasis disappears (experiment 4).

Brown, P., and Rothwell, J.C. (1997). Illusions of time. Society for Neuroscience abstracts: 27th annual meeting. 23 (2): 441.4: 1119. Yarrow, K., Haggard, P., Heal, R., Brown, P. & Rothwell, J.C. (2001). Illusory perceptions of space and time preserve cross-saccadic perceptual continuity. Nature, 414, 302-305.

Visible persistence, informational persistence, and visual short-term memory in change detection tasks
Filip Germeys and Caroline Van Eccelpoel
Laboratory of Experimental Psychology, University of Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Over the past ten years, research on 'change blindness', or the inability to detect changes to an object or scene, has grown steadily. Most of this work has focussed on the nature of our representations of the visual world. The striking inability to detect changes across blanks in the 'flicker' paradigm (an original and modified image are presented in alternation with a blank screen between them) and 'detection' paradigm (observers only receive one view of each image, separated by a blank) have mainly been interpreted as evidence for the idea that observers never form a complete, detailed representation of a scene. Furthermore, focussed attention is required to perceive change. In the absence of focussed attention, the contents of visual memory are simply overwritten by subsequent stimuli, and so cannot be used to make comparisons (Rensink, O'Regan, & Clark, 1997). Attention seems to insulate against the overwriting process, by transferring the item from a volatile to a more durable memory store (i.e. visual short-term memory, VSTM). The present study investigated the role of iconic memory (both visible persistence and informational persistence), attention, and VSTM in change detection. Five experiments using a change detection paradigm with arrays of letters, objects, or meaningless stimuli are presented.

Rensink, A., O'Regan, J. K., and Clark, J. J. (1997). To see or not to see: The need for attention to perceive changes in scenes. Psychological Science, 8, 368-373.

Probing the prerequisites of experimental 'blindness'
Michael Niedeggen1, Guido Hesselmann1, Arash Sahraie2, and Maarten Milders2
1 Experimental Psychology II, Duesseldorf, Germany
2
Department of Psychology, Aberdeen, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Using the technique of rapid serial visual presentation (RSVP), the conscious perception of coherently moving dots can be prevented. A brief transient 'motion blindness' is induced if subjects are asked to detect the presence of a local colour cue before switching attention to a global random-dot kinematogram. Essential for this effect is the presence of episodes of coherent motion (distractors) prior to the local colour cue. Using event-related brain potentials (ERPs) we examined which information processing stage is specifically affected by distractors. ERPs were separately analysed for three temporal distractor positions in the RSVP stream (early, medium, or late), and compared with two control conditions where the same motion stimuli were either relevant or irrelevant. A specific response was reflected in a frontal negativity at about 250 ms which increased with increasing number of motion distractors, and a centro-parietal positivity at about 350 ms which decrease with increased number of distractors. Early sensory processing, obtained in a posterior negativity at about 170 ms, remained unaffected. Our results suggest augmented activation in a frontal control system, triggered by distractors. This mechanism apparently prevents visual awareness, not by reducing the sensitivity in the visual cortex, but by gating to higher-order stimulus evaluation.

 

Wednesday 10 April 2002, 9:00 - 11:00,

Symposium 5 - Age of Acquisition and Written Language Processing: the Influence of Language and Orthography
Convenor
Ilhan Raman
Middlesex University, UK

Effects of age of acquisition in semantic categorisation tasks
Marc Brysbaert1, Mandy Ghyselinck2, and Gert Storms3
1. Royal Holloway, University of London, UK
2. Universiteit Gent, Belgium
3. Katholieke Universiteit Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The effect of AoA in visual word recognition is now firmly established. Most researchers interpret it as originating from the lexicon. However, Brysbaert, van Wijnendaele, and De Deyne (2000) ventured that AoA could also be an important variable in the way the semantic system is organised. It is not inconceivable that the meaning of later acquired concepts ishighly dependent on previously acquired concepts. Another possibility is that the conceptional core of a semantic category is formed by the first acquired instances of the category. We collected further evidence for the semantic hypothesis by carefully looking at the effect of AoA in categorisation tasks. Results show that AoA is a significant predictor of category verification times, with early-acquired words classified faster than later-acquired words.

Brysbaert, M., Van Wijnendaele, I., & De Deyne, S. (2000). Age-of-acquisition is a significant variable insemantic tasks. Acta Psychologica, 104, 215-226.

Effects of age of acquisition and word frequency on object naming, word naming andlexical decision in Spanish and English
Andrew W. Ellis1, Cristina Izura1, and Fernando Cuetos2
1. University of York, UK
2. University of Oviedo, Spain
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Ellis and Lambon-Ralph (2000) argued that effects of age of acquisition (AoA) should bestronger in tasks which involve arbitrary mappings between representations than in taskswhich involve consistent mappings. This prediction is tested in experiments whichinvolve picture naming and word naming for the same items in Spanish and English. AoA effects are stronger in object naming than word naming in both languages, but theexpectation that AoA effects would be larger in English than Spanish word naming wasnot upheld. Possible reasons for this are discussed. Effects of word frequency on the twotasks and languages are also considered.

Ellis, A. W. & Lambon-Ralph, M. A. (2000). Age of acquisition effects in adult lexical processing reflectloss of plasticity in maturing systems: Insights from connectionist networks. Journal of Experimental Psychology: Learning, Memory, and Cognition, 26, 1103-1123.

On the AoA effects and Orthographic Transparency: Evidence from Turkish
Ilhan Raman
Middlesex University, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

There has been a recent surge of interest in examining the effect of AoA on lexicalprocessing tasks, such as word naming. Evidence from English (e.g. Morrison & Ellis, 1997)suggests that, all other things equal, words acquired earlier tend to be named faster and moreaccurately than words acquired later on in life. More recently similar findings have emergedfrom orthographies other than English, namely, Dutch (Brysbaert, Van Wijnendaele, & DeDeyne, 2000), Spanish (Weekes, Saenz de Miera & Ioga, 2001) and Italian (Colombo, Brivio& Job, 2001). It is of importance to establish whether AoA could operate as a function oforthographic transparency by examining its effect on word naming in Turkish which has amore transparent orthography than those reported earlier. In a naming task adult skilledTurkish readers were required to name a total of 50 words that were matched on frequency,imageability, letter length, initial phoneme and number of syllables but were varied on AoA.The results indicate an effect for AoA despite the totally consistent, context independentnature of the Turkish writing system. This finding is discussed in view of current models oforal reading.

Brysbaert, M., Van Wijnendaele, I., & De Deyne, S. (2000). Age-of-acquisition is a significant variable insemantic tasks. Acta Psychologica, 104, 215-226.
Colombo, L., Brivio, C. & Job, R. (2001). On the interaction of age of acquisition and repetition. Paperpresented to the ESCOP, Edinburgh meeting, 5-8 September.
Morrison, C.M. & Ellis, A.W. (2000). Real AoA effects in word naming and lexical decision.BritishJournal of Psychology, 91, 167-180.
Weekes, B., Saenz de Miera, A. & Ioga, J.M. (2001). Age of Acquisition effects on reading and picturenaming in Spanish and English. Paper presented to the EPS, Manchester meeting, July 11-13.

ge of acquisition effects on spelling in surface dysgraphia
Brendan Weekes1, Robert Davies1, Ben Parris1, and Gail Robinson2
1. University of Sussex, UK
2. National Hospital for Neurology and Neurosurgery, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

One defining feature of surface dysgraphia is better spelling of words with predictablesound-to-spelling correspondences compared to words with unpredictablecorrespondences and a tendency to produce phonologically plausible errors (e.g. couch->COWTCH). These errors are often more marked for low frequency words than highfrequency words although this interaction is not always found (Graham, Patterson &Hodges, 2000). One concern is whether frequency effects are the result of age ofacquisition (AoA) effects given the high correlation between these two variables. We donot know whether AoA has an effect on spelling even though one dominant hypothesispredicts that AoA effects result from the activation of phonological representations. Oneway to explore this question is to test for AoA effects on spelling in surface dysgraphiasince it is universally assumed that surface dysgraphic patients spell words viaphonological representations (lexical or sublexical). We report MK a patient whosuffered Herpes Simplex Viral Encephalitis (HSVE) resulting in surface dysgraphia thatwe characterise as a tendency to produce a legitimate alternative spelling of amonosyllable defined as a LASC error. MK can access lexical and sublexicalphonological representations and we argue that he spells words using theserepresentations citing data to show that he cannot access orthographic lexemes directlyon written picture naming tasks. We report experiments designed 1) to test the effect ofAoA on MK's spelling by controlling for word frequency as well as other highlycorrelated variables using logistic regression and 2) to test the effects of AoA andpredictability on spelling using a fully factorial design. The results show an effect ofAoA but no effect of frequency and an interaction between AoA and predictability i.e. aneffect of AoA on unpredictable word spelling but no effect on predictable word spellingperformance. We discuss these data with reference to recent accounts of AoA locatingthe effect at the level of mappings between input and output representations (Ellis &Lambon-Ralph, 2000). We argue that the effect of AoA on spelling is not the result oflexeme activation per se but reflects instead the largely unpredictable mappings betweensound and spelling that exist in the majority of English words. We offer an account ofpredictability effects on spelling focused on competition between rime level units andargue that these effects reflect the normal cognitive processes used in spelling todictation.

Ellis, A.W. & Lambon-Ralph, M.A. (2000). Age of acquisition effects in adult lexical processing reflectsloss of plasticity in maturing systems: Insights from connectionist networks. Journal ofExperimental Psychology: Learning, Memory and Cognition, 26, 1103-1123.
Graham, N.L., Patterson, K., Hodges, J.R. (2000). The impact of semantic memory impairment on spelling:evidence from semantic dementia. Neuropsychologia, 38(2) 143-163.

Wednesday 10 April 2002, 9:00 - 12:30

Invited Symposium

Interaction of Implicit and Explicit Learning
Convenor
Eric Soetens
Vrije Universiteit Brussel, Belgium

How to survive without the implicit/explicit distinction
David R. Shanks
University College London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Implicit learning has been defined in terms of a lack of awareness of the process and productsof learning. Here I review evidence from a speeded target detection task, the serial reaction time(SRT) task, in which targets follow a structured sequence. Results obtained with this task havebeen taken to provide support for the existence of implicit learning and for its dissociation fromexplicit memory. This evidence suggests, for instance, (1) that response priming can bedissociated from explicit memory with the latter being indexed by the ability to recognize orgenerate the structured sequence, and (2) that amnesic individuals show normal primingcombined with impaired recognition. I present results from several new experiments whichsuggest, in contrast, that a single learning/memory system is adequate to account for performancein both normal and amnesic individuals. This conjecture is supported by a formal model whichis successful in describing the fine-detail of performance.

Another proposal is that the critical feature of implicit learning is that it proceeds without makingany demands on attentional resources. I review evidence from the SRT task for this proposal andpresent additional new results pertaining to it. These results show that secondary tasks impairsequence learning.

My overall conclusion is that as we approach the 50th anniversary of the study which initiatedexperimental research into the relationship between learning and awareness (Greenspoon, 1955),we are no closer to proving the existence of implicit learning.

Verbal report of incidentally experienced environmental regularity: the route from implicitlearning to verbal expression of what has been learned
Peter Frensch
Humbold University, Berlin, Germany
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In our research we focus on the mechanisms leading to participants' ability to verbally expressan environmental regularity that was experienced in the context of an incidental (implicit)learning situation. At present, our working hypothesis is that the ability to verbally describean incidentally experienced environmental regularity arises as a consequence of an intentionalsearch for the regularity. We believe further that the intentional search for regularity can betriggered by various means, one of which being the perceived consequence of implicitlearning (Unexpected-event Hypothesis).

The talk will be divided into two main parts. In the first part, I will discuss varioustheoretical ideas on how verbal report of an experienced environmental regularity comesabout. In the second part, I describe some of our own empirical research that directlyaddresses the empirical question at hand and is consistent with the claim that verbal report ofenvironmental regularity is the consequence of an intentional search for regularity.

The interaction of implicit and explicit sequence learning
Daniel B. Willingham
University of Virginia, USA
E-mail: " This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Over the last twenty years there has been a great deal of research directed at delineatingseparate systems of learning and memory. There has been less effort directed towardsdetermining how these systems might interact. I have suggested that implicit and explicitmemory operate in parallel, at least in motor skill learning. Explicit memory may guideongoing motor behavior while implicit learning occurs in the background, based on the actualmovements that are executed. I will present data from behavioral and from brain imagingparadigms in support of this idea. I will also present data relevant to the differences inrepresentation of implicit and explicit representations for motor skill. Finally, I will discussnew data from implicit and explicit learning of probabilistic categories, which others haveargued are mutually inhibitory.

Wednesday 10 April 2002, 14:30 - 16:30, Sessions 4, 5, 6

Session 4: Reading Faces

The "Who Said What" Paradigm Revisited: Insights from Multidimensional Scaling
Christophe Labiouse
University of Liege, Belgium & Belgian NFSR Research Fellow
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The original "Who Said What" paradigm was proposed by Taylor and colleagues (1978) and had provided an elegant tool to track issues related to social categorization. We propose some refinements to the original paradigm. A traditional element of the paradigm is that within-category differences are minimized and between-category differences are exaggerated. We show that this claim cannot be tested within the original framework. Therefore, instead of using real faces, we use morphed faces progressively modified by constant amounts between two face endpoints, and for which a priori baseline inter-similarities can be computed. In this way, we are able to test accentuation effects with the aid of multidimensional scaling. We use continua involving inter-ethnic faces. Evidence for social categorization and accentuation effects were found despite the absence of clear-cut categories, suggesting that people, even implicitly, exaggerate inter-categorical differences and reduce intra-categorical differences in order to cope with complex situations.

Putting names to faces: No theory seems to work.
Mike Burton, Rob Jenkins and Allan McNeill
University of Glasgow, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

It is well-established that retrieval of a person's name is generally harder (slower and more error prone) than retrieval of personal facts. Some recent theories have proposed that the difference between names and personal facts lies in the links between token makers and lemmas (e.g. Hollis & Valentine, 2001; Brédart et al, 1995). In essence, personal facts are stored in some semantic/conceptual system which in turn links to lemmas, whereas names have no semantic representation, and link to lemmas directly from token markers. This gives rise to the prediction that names should be easier to articulate than facts, when subjects are presented with a face. In two experiments we show that this prediction is not upheld. In common with other tasks comparing name and fact retrieval, subjects are slower to articulate names than facts, even when they are heavily over-trained on a small number of items (Experiment 1) or when the same words are used as facts or names (Experiment 2).

Brédart S, Valentine T, Calder A, Gassi L (1995). An interactive activation model of face naming. Quarterly Journal of Experimental Psychology, 48A, 466-486. Hollis J & Valentine T (2001). Proper-name processing: Are proper names pure referencing expressions? Journal of Experimental Psychology: Learning Memory and Cognition, 27, 99-116.

Reading the mind from eye gaze
Andrew J. Calder1, Andrew D. Lawrence1, Jill Keane1, Sophie Scott2, Adrian M. Owen1,Ingrid Christoffels3 and Andrew W. Young4
1
MRC Cognition and Brain Sciences Unit, University of Cambridge, UK
2
University College London, UK
3
University of Amsterdam, The Netherlands
4
University of York, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Baron-Cohen (1997) has suggested that the interpretation of gaze plays an important role in a normal functioning theory of mind system. Consistent with this suggestion, functional imaging research has shown that both theory of mind (ToM) tasks and eyegaze processing engage a similar region of posterior superior temporal sulcus (STS). However, a second brain region associated with ToM, the medial prefrontal cortex, has not been identified by previous eyegaze studies. We discuss the methodological issues that may account for the absence of medial prefrontal activation in these experiments and present a PET study that controls for these factors. Our experiment included three conditions in which the proportions of faces gazing at, and away from, the participant, were as follows: 100% direct (0% averted), 50% direct–50% averted, and 100% horizontally averted (0% direct). Two control conditions were also included in which the faces' gaze were averted down, or their eyes were closed. Contrasts comparing the gaze conditions with each of the control conditions revealed medial frontal involvement. Parametric analyses showed a significant linear relationship between increasing proportions of horizontally averted gaze and increased rCBF in the medial prefrontal cortex. The opposite parametric analysis (increasing proportions of direct gaze) was associated with increased rCBF in a number of areas including the superior and medial temporal gyri. Our results are consistent with the proposal that the presentation of highly social stimulus, such as gaze, is in itself sufficient to engage the mechanisms involved in attributing mental states to others.

Baron-Cohen, S. (1997). Mindblindness: An essay on autism and theory of mind. Cambridge, Masachusetts: MIT press.

The mentalistic significance of the mouth: A comparison of deaf and hearing children's use of mouth and eye information in schematic face reading.
L Jackson1, R Campbell2, and H Ellis3
1
University of Reading, UK
2 Human Communications Science, University College London, UK
3
Cardiff University, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In reading facial displays of emotion, deaf children may also attend more closely to mouth patterns than do hearing children (Jackson, 2000). We therefore hypothesised that a group of deaf children, predominantly from hearing families, may show idiosyncratic abilities in reading intention from schematic faces (The Charlie task - Baron-Cohen et al., 1995). After establishing that all these children were skilled at accurately indicating line of sight ('where is Charlie looking?'), some variants on the task were introduced. In Experiment 1, Charlie's line of sight was ambiguous, but the schematic mouth pattern indicated like ('smiley') or dislike ('sad') in relation to pictured objects of positive and negative valence. Both deaf and hearing children utilised mouth patterns to disambiguate eye gaze. Experiment 2 showed that deaf, but not hearing children, incorporated the schematic mouth pattern when inferring desire. This group of deaf children use the eyes to attribute mental states in a similar way to hearing children, despite indications that some deaf children have difficulty on ToM tasks dependent on reading 'the language of the eyes' (Jackson, 2000). They additionally take account of mouth patterns in reading faces to a greater extent than hearing children. Under these conditions, hearing, not deaf children, are blind to the 'mentalistic significance of the mouth'.

Baron-Cohen, S., Campbell, R., Karmiloff-Smith, A., Grant, J. & Walker, J. (1995). Are children with autism blind to the mentalistic significance of the eyes? British Journal of Developmental Psychology, 13, 379-398. Jackson, A. L. (2000). Do deaf children understand the language of the eyes? Paper presented at EPS conference, April 2000. Nottingham, UK.

Session 5: Thinking and Reasoning

Does everyone "take-the-best"? Empirical tests of a ‘fast and frugal' decision heuristic.
Ben R. Newell, David R. Shanks and Nicola J. Weston
University College London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The "Take-the-Best" (TTB) heuristic (e.g., G. Gigerenzer & D. G. Goldstein, 1996) states that when making a choice between two alternatives, people will base their choices solely on what they perceive as the most valid – or ‘best' – piece of information that discriminates between the alternatives. We report data from a series of experiments in which aspects of the experimental environment were manipulated to examine the parameters under which such a strategy operates. Clear evidence of TTB use was detected in all the experiments. However, the experiments also demonstrated that even under conditions contrived to promote the use of TTB – high cost of information, prior instruction as to the validity of cues, and a deterministic environment – there was a high proportion of behavior that was inconsistent with TTB. Together with the presence of large individual variability in strategy use in the experiments, these results question the validity of TTB as a psychologically plausible and pervasive model of behavior.

Gigerenzer, G., & Goldstein, D. G. (1996). Reasoning the fast and frugal way: Models of bounded rationality. Psychological Review, 103, 650-669.

Insensitivity to prior causal knowledge in inference
F. J. López1, A. Caño1, P. L. Cobos1, J. Almaraz1 and D. R. Shanks2
1
University of Málaga, Spain
2
University College London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In predictive causal inference people reason from causes to effects while in diagnostic inference they reason from effects to causes. Independently of the causal structure of the events, the temporal structure of the information provided to a reasoner may vary, e.g., multiple events followed by a single event versus a single event followed by multiple events. We report 2 experiments in which causal structure and temporal information were varied independently. The experiments use an overshadowing design that allows an unambigous evaluation of sensititvity to prior causal knowledge. The results reveal that inferences were influenced by the temporal but not by the causal structure of the task. These findings are relevant to the evaluation of two current accounts of causal induction, the Rescorla-Wagner (Rescorla & Wagner, 1972) and Causal Model theories (e.g., Waldmann & Holyoak, 1992).

Rescorla, R. A., & Wagner, A. R. (1972). A theory of Pavlovian conditioning: Variations in the effectiveness of reinforcement and nonreinforcement. In A. H. Black & W. F. Prokasy (Eds.), Classical conditioning II: Current theory and research, (pp. 64-99). New York: Appleton-Century-Crofts. Waldmann, M. R., & Holyoak, K. J. (1992). Predictive and diagnostic learning within causal models: Asymmetries in cue competition. Journal of Experimental Psychology: General, 121, 222-236.

Utilising threat: Anticipated regret in deontic reasoning
Nick Perham and Mike Oaksford
Cardiff University, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Three competing hypotheses were identified concerning the effects of varying threat material in deontic reasoning tasks, i.e., reasoning about what one should or should not do: attentional bias (Evans, 1996), decision theory (Manktelow & Over, 1991; Oaksford & Chater, 1994) and anticipated regret theory (Zeelenberg, van Dijk, Manstead, & van der Pligt, 2000). Experiment 1 discounted an attentional bias account because the effect of the threat material was observed for responses involving no explicit threat. Experiment 2 discounted standard decision theory, because it predicts similar effects when the threat material relates to a response that should be made as when it relates to a response that should not be made. However, equal and opposite effects were observed, which was only predicted by anticipated regret theory. The results showed that anticipated emotions affect deontic reasoning suggesting a productive theoretical synthesis of research in emotional decision making and deontic reasoning.

Evans, J. St.B. T. (1996). Deciding before you think: Relevance and reasoning in the selection task. British Journal of Psychology, 87, 223-240. Manktelow, K. I., & Over, D. E. (1991). Social roles and utilities in reasoning with deontic conditionals. Cognition, 39, 85-105. Oaksford, M., & Chater, N. (1994). A rational analysis of the selection task as optimal data selection. Psychological Review, 101, 608-631. Zeelenberg, M., van Dijk, W. W., Manstead, A. S. R., & van der Pligt, J. (2000). On bad decisions and disconfirmed expectancies: The psychology of regret and disappointment. Cognition and Emotion, 14(4), 521-541.

Dissociating memory processes underlying misinformation effects in young children.
Robyn Holliday
University of Kent at Canterbury, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

This study investigated the contribution of automatic and intentional memory processes to 4- and 5-year-old and 8- and 9-year-old children's acceptance of misleading suggestions. Children were presented with an event and this was followed the next day by a post-event summary containing misleading suggestions that were either read to participants or were self-generated in response to semantic and perceptual cues. Individual children were then given either a Structured Interview or a modified Cognitive Interview. A short time later, children were asked a series of yes / no questions on their memories for the video story under two instruction conditions (cf. Holliday & Hayes, 2000). In the inclusion condition children reported whether they remembered details from either the video or the post-event summary phases. In the exclusion condition children were instructed to exclude post-event suggestions. Evidence of a misinformation effect was found in both age groups. Moreover, children were more likely to accept misled-generated items compared to misled-read items in the inclusion condition, but the opposite was the case under exclusion instructions. Process dissociation analyses (cf. Holliday & Hayes, 2000, 2001; Jacoby, 1991) revealed that both automatic and intentional processes influenced misinformation acceptance, but that suggestibility was predominantly due to automatic processes. These findings support a dual-process theory of misinformation acceptance in children (cf. Brainerd & Reyna, 1998). Competing models of the misinformation effect in children are evaluated in the light of these findings.

Holliday, R. E., & Hayes, B. K. (2000). Dissociating automatic and intentional processes in children's eyewitness memory. Journal of Experimental Child Psychology, 75, 1-42. Holliday, R. E., & Hayes, B. K. (2001). Automatic and intentional processes in children's eyewitness suggestibility. Cognitive Development, 16, 617-636. Jacoby, L. L. (1991). A process dissociation framework: Separating automatic from intentional uses of memory. Journal of Memory and Language, 30, 513-541.

Session 6: Tracing Processing through Fixations and Saccades

Fixation positions on words in English sentences.
Sarah J. White and Simon P. Liversedge
University of Durham, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Two experiments investigated the effect of orthographic regularity on first fixation landing positions and refixations on words in English sentences. In Experiment One, the first or second letters of words were misspelled. The misspellings formed frequent or infrequent word initial trigrams. The critical words were embedded within the same sentence frame for all of the conditions. First fixation landing positions were significantly nearer the word beginning for all of the misspelled conditions compared to the correctly spelled condition. Also, the second of multiple fixations was more likely to be to the left of the initial landing position for two of the misspelled conditions compared to the correctly spelled condition. In Experiment Two all of the words were spelled correctly. The critical words began with either high or low type and token frequency bigrams and trigrams. The critical words were matched for word length and embedded within the same sentence frame up to the word after the critical word. For saccades launched from near launch sites, landing positions were significantly nearer the word beginning for words with infrequent initial letter sequences. The results will be discussed in relation to current models of eye movements in reading.

Searching for information: Eye movements while attempting to verify statements about pictorial scenes
Geoffrey Underwood, Lorraine Bell and Kate Roberts
University of Nottingham, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Eye movements were recorded while 24 participants either searched for specific parts of a scene that would enable them to verify a previously read statement, or they first inspected the scene in preparation for the sentence verification task. The sentences made simple declarative statements about the events depicted in photographs of natural scenes. The order of presentation of picture and sentence was reflected in the fixation measures on both types of stimuli. When the sentence was read after the picture, average fixation durations and overall reading times were longer than when it was read before seeing the picture. The number of fixations, and overall inspection times on the picture were longest when they were seen before the sentence. These patterns reflect differences between general inspection and a specific search.

Bottom-up and top-down control in visual search
Wieske van Zoest and Mieke Donk
Vrije Universiteit Amsterdam, The Netherlands
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Previous research suggests that visual selection is controlled either in a bottom-up or in a top-down manner. However, possibly both manners of control simultaneously determine visual selection. To date, no studies have been performed to estimate the relative importance of top-down and bottom-up control in visual search. In the present study observers were presented with search displays consisting of an array of line segments that were rotated at various orientations. The task of observers was to indicate the presence of a vertical line segment (the target) presented amongst a series of nontargets and one distractor. Manual reaction times and eye movements were recorded. By varying the absolute differences in orientation between the target, nontargets and distractors, relative target-distractor saliency and target-distractor similarity were independently manipulated to investigate the relative contribution of bottom-up and top-down control. The major result was that relative target-distractor saliency and target-distractor similarity affected search performance independently.

Saccadic responses indicate parallel set activation during task-switching
Charlotte Golding, Tim Hodgson, and Chris Kennard
Imperial College, London, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

When participants switch between tasks they reliably incur a time penalty (switch cost) which may reflect a discrete processing event of task-reconfiguration that is completed by the end of the first trial after a switch (e.g. Rogers & Monsell, 1995 and Goschke, 2000). However, we (Golding et al., 2001) reported evidence of switch costs persisting beyond the switch trial. Here we investigate further subtle effects task-switching has on saccade trajectories. In a computer-generated card sorting test participants matched a central card to one of 3 outer cards according to a pre-cued perceptual dimension (shape-matching or colour-matching task). Switching disrupted efficient search, causing an increase in: the initial saccade's latency; the number of saccades and the bias of the initial saccade towards the relevant distractor. All of these switch costs persisted beyond the switch trial. Moreover, in both the switch and subsequent trial, the first saccade was frequently hypometric and followed by a secondary saccade to the target after a brief (<100ms) fixation. These hypometric saccades had abnormally high peak velocities, suggesting that they were truncated; their execution having been interrupted by the prior programming of the second saccade (McPeek et al., 2000). Such parallel processing of saccades to targets for both tasks is inconsistent with the serial stage models of task-reconfiguration.

Wednesday 10-04-02, 17:00 - 18:30, Sessions 7, 8, 9

Session 7: Modeling Semantic Structure

Verbal fluency from common and ad hoc categories: evidence from dementia
Arlene J. Astell1 and Romola S. Bucks2
1
University of St. Andrews, UK
2
University of Southampton, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Category fluency, generation strategy, generation stability, fluency following prompting and category judgement are examined in three studies with people with dementia of the Alzheimer-type (DAT). The same eight categories are used throughout, four common and four ad hoc. As previously reported, category fluency is reduced in DAT relative to controls. However, it is more impaired for common categories than ad hoc categories. There is also differential usage of generation strategies, with the DAT participants making more use of experiential strategies than semantic ones. In addition, strategy prompting is found to assist in the generation of additional items in DAT. Category judgement is largely intact in the DAT participants for both common and ad hoc categories, even for low frequency or uncommon items. These findings taken together suggest that item knowledge is relatively well preserved in DAT. As such, observed difficulties in retrieving item information may be attributable to impairments in the processes that act on stored information in the verbal fluency task.

Conceptual structure in the normal system: Domain differences in the time course of activation of correlated and non-correlated semantic information.
Billi Randall, Helen Moss and Lorraine K. Tyler
Centre for Speech and Language, Department of Experimental Psychology, University of Cambridge, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

We have recently developed an account of conceptual representation in which the structure of concepts differs systematically across domains and categories of knowledge in terms of the relative distinctiveness of semantic properties and the patterns of intercorrelation among them. Support for the Conceptual Structure Account has been derived from patterns of impaired and intact knowledge in patients with category-specific deficits and from neuroimaging studies (Tyler & Moss, 2001).

The current study explored the model's implications for the time course of activation of conceptual information in the normal system. We predicted that the activation of distinctive properties of living things (e.g. elephant – has a trunk) would be delayed relative to that of shared properties (e.g. elephant –has legs) due to their paucity of correlations with other features. This prediction was supported in a speeded (respond-to-deadline) feature verification task. In a second experiment, where presentation was slower and there was no response deadline, no such differences between living and non-living things were observed, consistent with the view that in the normal system correlational structure affects the initial activation of information rather than its eventual state.

L.K. Tyler & H.E. Moss (2001). Towards a distributed account of conceptual knowledge. Trends in Cognitive Sciences, 5.6, 244-252.

On the Use of Scaling and Clustering in the Study of Semantic Disruptions in Patients with Alzheimer's Disease
Gert Storms1, Trinette Dirikx1, Jos Saerens2, 3, Sonja Verstraeten2, 3 and Peter P. De Deyn 2, 3
1
Department of Psychology, University of Leuven, Belgium
2
Memory Clinic, General Hospital Middelheim, Antwerp, Belgium
3
Laboratory of Neurochemistry and Behavior, Born Bunge Foundation, University ofAntwerp, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

In the past decade, several studies have used scaling and clustering techniques to document semantic deficits in patients with Alzheimer's disease. In this presentation we argue that many of the conclusions drawn from these studies are unjustified by the data. We review the methodology used in these studies and present data from simulation studies to further investigate the validity of their conclusions. We also present empirical data from patients and normal control subjects to demonstrate that analyses of the patients' proximity data do not provide unambiguous evidence for a generalized semantic deficit.

Session 8: Phonology in Speech and Reading

In pursuit of the Syllabary: this Snark is a Boojum!
Stephen Monsell, Arie van der Lugt and Patricia Jessiman
University of Exeter, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Some speech production theorists, notably Levelt, Roelofs and Meyer (1999), have proposed that during the translation of abstract phonological sequences into articulatory motor activity, the speaker retrieves articulatory "gestural scores" for familiar syllables from a "syllabary". That the speech-motor system learns and retrieves frequent patterns rather than recomputes them is plausible and would solve part of the coarticulation problem. But evidence for the existence of a syllabary has been in short supply. We report three attempts to demonstrate the contribution of the syllabary to speech production. We failed to find more rapid picture naming for words whose constituent syllables had just been primed by a production in another word. We failed to find any difference in the rapid production of prepared utterances consisting of matched nonword sequences composed of frequent syllables versus syllables that do not occur in English. We found only a tiny difference in the latency for naming visually presented syllables of these two kinds, matched for orthographic difficulty. Either there is no syllabary, or the advantage it confers in production is very small.

Levelt W.M., Roelofs, A., Meyer, A.S. (1999) A theory of lexical access in speech production. Behavioral and Brain Sciences, 22, 1-75.

The role of the rime. A cross-linguistic comparison of rime effects in reading English and Dutch
Dominiek Sandra1, James Booth2, Heike Martensen1, Astrid Geudens1 and Charles Perfetti3
1
University of Antwerp, Centre for Psycholinguistics, Belgium
2
Northwestern University, USA
3
University of Pittsburgh, USA
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Orthographies differ in the consistency of their grapheme-to-phoneme mappings. GP mappings are rather inconsistent in English (beat, bear) but quite consistent in Dutch. In English, consistency between orthography and phonology increases considerably at the rime level (fight, light). Such cross-linguistic differences might explain why rime effects were not found in Dutch (Geudens & Sandra, 1999; Martensen, Loncke & Sandra, in prep.). However, Booth & Perfetti's (2001) results suggest that even in English, rime effects do not reveal early recognition units in lexical processing (equal effects of rimes and non-rimes in brief identication) but depend on phonological assembly for reading aloud (effect in naming). We investigated this issue cross-linguistically, by comparing a language whose orthography-to-phonology mappings are quite reliable at the grapheme level (Dutch) to one in which such reliability emerges at the rime level (English). A masked priming paradigm was used to study the effect of VC primes on CVC targets, using brief identification and naming tasks (frequency-matching across languages). We obtained equal priming effects for Dutch and English in brief identification and no effects in naming. In Dutch, but not in English, a correlation between CV frequency and naming times was found. Follow-up experiments with CV primes are planned.

Lexical Bias in Spoonerisms: a 'related beply' to Baars, Motley, and MacKay (1975)
Robert J. Hartsuiker1, Martin Corley1, and Heike Martensen2
1
University of Edinburgh, UK
2
University of Antwerp, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Phonological speech errors occur more often when they form real words than nonwords. This 'lexical bias' effect has been taken as evidence for phoneme-to-word form feedback in word production, but also as evidence for pre-articulatory editing. The latter account seemed to be supported by the finding that the effect is modified by context (Baars et al., 1975). We further explored such context effects in order to test the editing account. We used a speeded naming task of nonword pairs ("pood gath") to elicit spoonerisms (responding "good path"). Critical items were all nonwords and either resulted in words when spoonerized (pood gath) or not (pooth gad). The critical items were either embedded in mixed lists of words and nonwords or in a pure nonword context. In the mixed condition, nonword pairs with lexical outcome (pood gath) were spoonerized more often than nonword pairs with nonlexical outcome (pooth gad). This lexical bias effect disappeared in the pure nonword condition. Inconsistent with an editing account, we observed that lexical context increased the number of word outcomes, rather than decreased the number of nonword outcomes. We tentatively propose the alternative explanation that context influences the probability to misread nonword targets as real words.

Session 9: Object Discrimination

Context-dependent asymmetries in stimulus comparisons by monkeys
Hans Op de Beeck1, 2, Johan Wagemans2, and Rufin Vogels1
1
Laboratory of Neuro- en Psychofysiology, University of Leuven, Belgium
2
Laboratory of Experimental Psychology, University of Leuven, Belgium
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Similarity is a core concept in theories of object recognition, categorization, and reasoning. It is often conceptualized as a geometric distance in a multidimensional stimulus space. However, research in humans has revealed that similarity judgments involve more than a simple distance calculation (e.g., Tversky, 1977, Psychological Review). Contrary to the central asumptions in geometric models, similarity judgments are asymmetric when stimuli differ in their prototypicality or salience. For example, most people judge Mexico to be more similar to USA than USA to Mexico. Here we provide the first evidence for marked asymmetries in nonhuman species. We trained two rhesus monkeys in a temporal same/different task with a parametric control of stimulus prototypicality. The monkeys made most errors ('same' responses) when the first stimulus in a trial was less prototypical than the second one. This effect of prototypicality became remarkably fine-tuned as the monkeys acquired more experience with the stimulus set: In the beginning of the experiment the asymnmetries were sensitive to prototypicality in the context of the total set of stimuli, whereas the prototypicality for more local regions in stimulus space mattered in later sessions. We conclude that asymmetric similarity judgments also occur in non-verbal animals, and that they do so with a high sensitivity for stimulus statistics.

Advantage of low visual acuity of the retina in 2-month-olds infants: a statistical categorization model
Martial Mermillod1, Robert M. French1, Paul C. Quinn2, and Denis Mareschal3
1
University of Liège, Belgium
2
Washington & Jefferson College, USA
3 Birkbeck College, UK
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

From the earliest moments of postnatal development, perceptual maturation is believed to place a functional constraint on the ability to recognize or categorize stimuli from the environment. Using a computer simulation of retino-cortical development, with a bank of Gabor wavelets providing the output of the V1 complex cells, we showed that reducing the range of spatial frequencies from the retinal map allows better categorization performances for a statistical model. The simulations provide a pattern of statistical data showing that a statistical categorization model may be more efficient with low visual acuity retina. Moreover, we have found that this effect interacts with the type of category in such a way that super-ordinate level categories are enhanced by the simulated low visual acuity of 2-month-old infants whereas basic level categories are less or equally categorized with the low visual acuity. These data are convergent with empirical data showing that 2-month-olds infants acquired earlier and more easily super-ordinate level categories than basic level categories (Quinn & Johnson, 2000).

Interactions between view changes and shape changes in picture-picture matching
Rebecca Lawson1, Heinrich H. Bülthoff2 and Sarah Dumbell1
1
University of Liverpool, UK
2
Max Planck Institut, Tübingen, Germany
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Four studies presented pictures of different morphs of novel, complex, three-dimensional objects, similar to objects which we must identify in the real world. We investigated how viewpoint changes influence our ability to discriminate between morphs. View changes had a powerful effect on performance in picture-picture matching tasks when similarly shaped morphs had to be discriminated. Shape changes were detected faster and more accurately when morphs were depicted from the same rather than different views. In contrast, view change had no effect when dissimilarly shaped morphs had to be discriminated. This interaction between the effects of view change and shape change was found for both simultaneous stimulus presentation and for sequential presentation with interstimulus intervals of up to 3600ms. The interaction was found following repeated presentations of the stimuli prior to the matching task and following practice at the matching task as well as after no such pre-exposure to the stimuli or to the task. The results demonstrate the importance of view changes relative to other task manipulations in modulating the shape discrimination abilities of the human visual recognition system.