![]() |
"A Laterally Interconnected Neural Architecture in MST Accounts for Psychophysical Discrimination of Complex Motion Patterns" |
![]() |
Scott A. Beardsley & Lucia M. Vaina
Brain & Vision Research Laboratory
Department of Biomedical Engineering
Boston University
Boston MA 02215
USA
The complex patterns of visual motion formed across the retina
during self-motion, often referred to as "optic flow", provide a rich
source of information describing our dynamic relationship within the
environment. Psychophysical studies indicate the existence of specialized
detectors for component motion patterns (radial, circular, planar)
that are consistent with the visual motion properties of cells in the
medial superior temporal area (MST) of non-human primates. Here we use
computational modeling and psychophysics to investigate the structural
and functional role of these specialized detectors in performing a graded
motion pattern (GMP) discrimination task. In the psychophysical task
perceptual discrimination varied significantly with the type of motion
pattern presented, suggesting perceptual correlates to the preferred
motion bias reported in MST. Simulated perceptual discrimination in a
population of independent MST-like neural responses showed inconsistent
psychophysical performance that varied as a function of the visual motion
properties within the population code. Robust psychophysical performance
was achieved by fully interconnecting neural populations such that they
inhibited non-preferred units. Taken together, these results suggest
that robust processing of the complex motion patterns associated with
self-motion and optic flow may be mediated by an inhibitory structure
of neural interactions in MST.