© 2003 Nature Publishing Group

HIGHLIGHTS

NATURE REVIEWS | NEUROSCIENCE VOLUME 4 | APRIL 2003 | 243

HIGHLIGHT ADVISORS

NANCY ANDREASEN

UNIVERSITY OF IOWA, IA, USA

ALLAN BASBAUM

UNIVERSITY OF CALIFORNIASAN FRANCISCO, CA, USA

RANDY BUCKNER

WASHINGTON UNIVERSITY,MO, USA

DAVID CLAPHAM

HARVARD MEDICAL SCHOOL,MA, USA

PIETRO DE CAMILLI

YALE UNIVERSITY SCHOOL OFMEDICINE, CT, USA

BARRY EVERITT

UNIVERSITY OF CAMBRIDGE,UK

GORDON FISHELL

SKIRBALL INSTITUTE, NY, USA

MARY KENNEDY

CALIFORNIA INSTITUTE OFTECHNOLOGY, CA, USA

LYNN NADEL

UNIVERSITY OF ARIZONA,

AZ, USA

DENNIS O’LEARY

THE SALK INSTITUTE, CA, USA

TERRY SEJNOWSKI

THE SALK INSTITUTE, CA, USA

WOLF SINGER

MAX-PLANCK-INSTITUT FÜRHIRNFORSCHUNG, GERMANY

CLAUDIO STERN

UNIVERSITY COLLEGE LONDON,UK

PATRICK TAM

CHILDREN'S MEDICALRESEARCH INSTITUTE, SYDNEY,AUSTRALIA

RICHARD W. TSIEN

STANFORD UNIVERSITYSCHOOL OF MEDICINE, CA, USA

RAFAEL YUSTE

COLUMBIA UNIVERSITY, NY, USA

The human fusiform gyrus is specifi-cally activated in response to faces.This observation has led to the ideathat face processing takes place sepa-rately from that of other objects in aface-specific processing module. Butthere is evidence that such a modulemight not be so specific, as thefusiform area can also show similaractivations in response to birds, carsor other objects in people with exper-tise on these stimuli. So far, it has notbeen possible to determine if the acti-vation measured in response to facesand other objects recruits the samenetwork, or nearby networks thatwork in parallel. Gauthier et al. havenow approached this problem byexploring whether processing ofobjects on which people are expertsinterferes with processing of faces.

The authors reasoned that if thesame networks process faces andother objects, then processing of onestimulus should interfere with pro-cessing of the other when subjects arerequired to handle both categoriessimultaneously. They thereforedevised a test in which subjects sawalternating pictures of faces and cars,and were required to say if the bottomhalf of an image was the same or dif-ferent than the one before of the samecategory.As we all are experts on faces,our processing of the bottom part of aface tends to be affected by the tophalf; we process faces as a whole.Gauthier et al. took advantage of this‘holistic processing’ to explorewhether car experts also processedcars in a holistic manner, and whether

processing pictures of cars interferedwith their judgement of faces. Theyfound that car processing was indeedholistic and interfered with face pro-cessing. In addition, the level of inter-ference correlated with the degree ofexpertise. The authors also measuredan event-related potential (the N170),which tends to be larger in response tofaces than to other objects, andobserved that this potential was largerin car experts than in novices whenseeing cars. More importantly, theyfound that an index of interference in terms of the N170 amplitude also correlated with the degree of expertise.

These results provide behaviouraland electrophysiological evidenceagainst the idea that there is a face-specific processing module. Moreover,as the N170 occurs quite early duringvisual processing, the data indicatethat the lack of functional indepen-dence between the processing of facesand other objects becomes manifestduring the initial, perceptual stages ofvisual processing.

Juan Carlos López

References and linksORIGINAL RESEARCH PAPER Gauthier, I. et al.Perceptual interference supports a non-modularaccount of face processing. Nature Neurosci.10 March 2003 (doi:10.1038/nn1029)

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