Simulation of orientation preference in the LGS model using type I connectivity. In this experiment the network was stimulated with moving bars only.
A: (top) Retinal image of line projected onto retina, which then supplies the retinotopic inputs into the non-granular layers
A: (bottom) Raw image of cortical activity in the non-granular layers. Grey levels show the activation level due to the direct and indirect inputs, as modified by the excitatory-centre / inhibitory-surround mechanism. The activation varies from 0 (white) to 1.5 (black).
B: False colour map of orientation preference. The map is produced in a manner analogous to the orientation preference maps in vivo. Orientation preference varies from 0 to pi. Detail to the right of this figure shows singularities, linear zones and saddle-points.
C: Regions in which the orientation selectivity was low also show highest rate of change in orientation preference.