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- C. Piepenbrock
and K. Obermayer. The Role of Lateral Cortical Competition in Ocular
Dominance Development.
.
In Advances in Neural Information Processing Systems 11, pages
139-145, Cambridge, Massachusetts, 1999. MIT Press.
(FTP Gzipped PostScript, 7 pages, 92 kb)
Lateral competition within a layer of neurons sharpens and
localizes the response to an input stimulus. Here, we investigate a model for
the activity dependent development of ocular dominance maps which allows to
vary the degree of lateral competition. For weak competition, it resembles a
correlation-based learning model and for strong competition, it becomes a
self-organizing map. Thus, in the regime of weak competition the receptive
fields are shaped by the second order statistics of the input patterns,
whereas in the regime of strong competition, the higher moments and
``features of the individual patterns become important. When correlated
localized stimuli from two eyes drive the cortical development we find (i)
that a topographic map and binocular, localized receptive fields emerge when
the degree of competition exceeds a critical value and (ii) that receptive
fields exhibit eye dominance beyond a second critical value. For
anti-correlated activity between the eyes, the second order statistics drive
the system to develop ocular dominance even for weak competition, but no
topography emerges. Topography is established only beyond a critical degree
of competition.
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