Event

Title: Guy Wallis/Ulrike Siebeck
Start date: Apr 18 2017
Start time: 11:15 am
End time: 12:15 pm
Organizer: Ksander de Winkel
Location: MRZ seminar room
Description: 

Abstract: Our understanding of the mechanisms and neural substrates underlying visual recognition has made considerable progress over the past 30 years. During this period, accumulating evidence has led many scientists to conclude that objects and faces are recognised in fundamentally distinct ways, and in fundamentally distinct cortical areas. The work described in this talk attempts to reconcile these differences by considering the effects of learning. In the first half of the talk we describe how a widely accepted, self-organizing model of object recognition is affected by repeated exposure to specific stimulus classes. In so doing, we explain how many aspects of recognition generally regarded as unusual to faces (holistic processing, configural processing, sensitivity to inversion, the other-race effect, the prototype effect, caricaturing) are emergent properties of category-specific learning within such a system. In the second half of the talk we describe a series of behavioural experiments involving a range of fish species. Using operant conditioning we have successfully trained fish to discriminate both fish and human faces, requiring them to learn a diverse range of behavioural tasks (2AFC, odd-one-out, 4AFC) through which they demonstrate a range of visual abilities (tolerance to view-changes, categorical perception). Given the fact that these fish lack a cortex, experiments of this kind can help constrain models of recognition and tell us more about what cortex is actually for.

PROFESSOR GUY WALLIS
Centre for Sensorimotor Performance
School of Human Movement and Nutrition Sciences
The University of Queensland

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