The Journal of Neuroscience, 0000, 20:RC86:1-6
RAPID COMMUNICATION
Orientation Formed by a Spot's Trajectory: A Two-Dimensional
Population Approach in Primary Visual Cortex
Dirk
Jancke
Institut für Neuroinformatik, Theoretische Biologie,
Ruhr-Universität, D-44780 Bochum, Germany
There exist a large number of visual illusions indicating that
perception differs from pure representation of physical input. For
example, a spot of light can be characterized by its position, but it
does not contribute any information about orientation. However, when
moved fast enough, a continuous streak along its trajectory is
perceived that helps to determine the orientation of the movement path.
The question arises whether the processing of the trajectory and its
orientation are simultaneously represented in the primary visual
cortex. Here I show that decoding neural population activity within a
two-dimensional parameter space represents both (1) physical input
given by the actual position of the moving spot and (2) orientation.
This latter parameter has no physical counterpart in the stimulus but
must be actively formed by spatiotemporal integration of the spot's trajectory.
Key words:
cat; interaction; motion streak; neural ensembles; orientation preference; population code; population dynamics; receptive
field; striate cortex; visual field
Copyright © 0000 Society for Neuroscience 0270-6474/00/$05.00/0