Abstract:
:Within a linear field approach, an architectural model for simple cell direction selectivity in the visual cortex is proposed. The origin of direction selectivity is related to recurrent intracortical interactions with a spatially asymmetric character along the axis of stimulus motion. No explicit asymmetric temporal mechanisms are introduced or adopted. The analytical investigation of network behavior, carried out under the assumption of a linear superposition of geniculate and intracortical contributions, shows that motion sensitivity of the resulting receptive fields emerges as a dynamic property of the cortical network without any feed-forward direction selectivity bias. A detailed analysis of the effects of the architectural characteristics of the cortical network on directionality and velocity-response curves was conducted by systematically varying the model's parameters.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Sabatini SP,Solari Fdoi
10.1007/s004220050515keywords:
subject
Has Abstractpub_date
1999-03-01 00:00:00pages
171-83issue
3eissn
0340-1200issn
1432-0770journal_volume
80pub_type
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