Recent papers on perception and neurodynamics

[DeLiang Wang]

The following papers, available at
http://www.cis.ohio-state.edu/~dwang/announce.html,
may be of interest to the list:

1. Liu X. and Wang D.L. (1999): "Perceptual organization based on temporal
dynamics." Proceedings of NIPS-99, in press.

A figure-ground segregation network is proposed based on a novel boundary pair
representation. Nodes in the network are boundary segments obtained through
local grouping. Each node is excitatorily coupled with the neighboring nodes
that belong to the same region, and inhibitorily coupled with the corresponding
paired node.  Gestalt grouping rules are incorporated by modulating
connections.  The status of a node represents its probability being figural and
is updated according to a differential equation.  The system solves the
figure-ground segregation problem through temporal evolution.  Different
perceptual phenomena, such as modal and amodal completion, virtual contours,
grouping and shape decomposition are then explained through local diffusion.
The system eliminates combinatorial optimization and accounts for many
psychophysical results with a fixed set of parameters.


2. Wang D.L. (2000): "On connectedness: a solution based on
oscillatory correlation." Neural Computation, vol. 12,
pp. 131-139.

A long-standing problem in neural computation has been the problem of
connectedness, first identified by Minsky and Papert in 1969.  This problem
served as the cornerstone for them to analytically establish that perceptrons
are fundamentally limited in computing geometrical (topological) properties.  A
solution to this problem is offered by a different class of neural networks -
oscillator networks.  To solve the problem, the representation of oscillatory
correlation is employed whereby one pattern is represented as a synchronized
block of oscillators, and different patterns are represented by distinct blocks
that desynchronize from each other.  Oscillatory correlation emerges from a
LEGION network, whose architecture consists of local excitation and global
inhibition among neural oscillators.  It is further shown that these oscillator
networks exhibit sensitivity to topological structure, which may lay a
neurocomputational foundation for explaining the psychophysical phenomenon of
topological perception.


3. Wang D.L. (1999): Relaxation oscillators and networks. In Webster J.
(ed.), Wiley Encyclopedia of Electrical and Electronics Engineering,
Wiley & Sons, vol. 18, pp. 396-405.

A tutorial article on oscillatory dynamics and its applications to auditory and
visual scene analysis.

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Dr. DeLiang Wang
Department of Computer and Information Science
The Ohio State University
2015 Neil Ave.
Columbus, OH 43210-1277, U.S.A.

Email: dwang at cis.ohio-state.edu
Phone: 614-292-6827 (OFFICE); 614-292-7402 (LAB)
Fax: 614-292-2911
URL: http://www.cis.ohio-state.edu/~dwang