UCL  IRIS
Institutional Research Information Service
UCL Logo
Please report any queries concerning the funding data grouped in the sections named "Externally Awarded" or "Internally Disbursed" (shown on the profile page) to your Research Finance Administrator. Your can find your Research Finance Administrator at http://www.ucl.ac.uk/finance/research/post_award/post_award_contacts.php by entering your department
Please report any queries concerning the student data shown on the profile page to:

Email: portico-services@ucl.ac.uk

Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
Publication Detail
The Neural Correlates of Crowding-Induced Changes in Appearance
Abstract
Object recognition in the peripheral visual field is limited by crowding: the disruptive influence of nearby clutter [1, 2]. Despite its severity, little is known about the cortical locus of crowding. Here, we examined the neural correlates of crowding by combining event-related fMRI adaptation with a change-detection paradigm [3]. Crowding can change the appearance of objects, such that items become perceptually matched to surrounding objects; we used this change in appearance as a signature of crowding and measured brain activity that correlated with the crowded percept. Observers adapted to a peripheral patch of noise surrounded by four Gabor flankers. When crowded, the noise appears oriented and perceptually indistinguishable from the flankers. Consequently, substituting the noise for a Gabor identical to the flankers ('change-same') is rarely detected, whereas substituting for an orthogonal Gabor ('change-different') is rarely missed. We predicted that brain areas representing the crowded percept would show repetition-suppression on 'change-same' trials, but release from adaptation on 'change-different' trials. This predicted pattern was observed throughout V1-V4, increasing in strength from early to late visual areas. These results depict crowding as a multi-stage process, involving even the earliest cortical visual areas, with perceptual consequences that are increasingly influenced by later visual areas.
Publication data is maintained in RPS. Visit https://rps.ucl.ac.uk
 More search options
UCL Researchers Show More
Author
Inst Ophthalmology - Visual Neuroscience
Author
Institute of Ophthalmology
Author
Experimental Psychology
Author
Faculty of Life Sciences
University College London - Gower Street - London - WC1E 6BT Tel:+44 (0)20 7679 2000

© UCL 1999–2011

Search by