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Competition and selection during visual processing of natural scenes and objects

VanRullen, Rufin and Koch, Christof (2003) Competition and selection during visual processing of natural scenes and objects. Journal of Vision, 3 (1). Art. no. 8. ISSN 1534-7362.

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When a visual scene, containing many discrete objects, is presented to our retinae, only a subset of these objects will be explicitly represented in visual awareness. The number of objects accessing short-term visual memory might be even smaller. Finally, it is not known to what extent “ignored” objects (those that do not enter visual awareness) will be processed –or recognized. By combining free recall, forced-choice recognition and visual priming paradigms for the same natural visual scenes and subjects, we were able to estimate these numbers, and provide insights as to the fate of objects that are not explicitly recognized in a single fixation. When presented for 250 ms with a scene containing 10 distinct objects, human observers can remember up to 4 objects with full confidence, and between 2 and 3 more when forced to guess. Importantly, the objects that the subjects consistently failed to report elicited a significant negative priming effect when presented in a subsequent task, suggesting that their identity was represented in high-level cortical areas of the visual system, before the corresponding neural activity was suppressed during attentional selection. These results shed light on neural mechanisms of attentional competition, and representational capacity at different levels of the human visual system.

Item Type:Article
Related URLs:
URLURL TypeDescription DOIArticle
VanRullen, Rufin0000-0002-3611-7716
Koch, Christof0000-0001-6482-8067
Additional Information:© 2003 by The Association for Research in Vision and Ophthalmology. Received August 7, 2002; published February 11, 2003. This research was supported by grants from the NSF-sponsored Engineering Research Center at Caltech, the National Institutes of Health and the W.M. Keck Foundation Fund for Discovery in Basic Medical Research. R.V. is supported by a fellowship from the California Institute of Technology. The initial idea for this experiment emerged from discussions with Francis Crick and Nikos Logothetis. The authors wish to thank L. Reddy and P. Wilken, as well as Dan Simons and one anonymous reviewer for useful comments on the manuscript. Commercial relationships: None.
Group:Koch Laboratory (KLAB)
Funding AgencyGrant Number
Center for Neuromorphic Systems Engineering, CaltechUNSPECIFIED
W. M. Keck FoundationUNSPECIFIED
Subject Keywords:attention, competition, capacity, negative priming, natural scenes
Issue or Number:1
Record Number:CaltechAUTHORS:RULjov03
Persistent URL:
Official Citation:VanRullen, R., & Koch, C. (2003). Competition and selection during visual processing of natural scenes and objects. Journal of Vision, 3(1):8, 75-85,, doi:10.1167/3.1.8.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7654
Deposited By: Archive Administrator
Deposited On:20 Mar 2007
Last Modified:02 Oct 2019 23:44

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