SIMULATION OF DYNAMIC RECEPTIVE-FIELDS IN PRIMARY VISUAL-CORTEX

A model network of spiking neurons with lateral connections was used t o simulate short-term receptive field (RF) changes by removal of affer ent input in the primary visual system. Several possible mechanisms fo r the dynamic RFs were explored and the simulation results were compar ed with experimental results obtained by Pettet and Gilbert [(1992) Pr oceedings of the National Academy of Science, U.S.A., 89, 8366-8370]. We found that appropriate input stimuli could induce a shift in the ba lance between modeled cortical lateral excitation and inhibition and i n doing so cause RF expansion. Synaptic plasticity was neither necessa ry nor appropriate for short-term RF changes. An inhibition dominant n etwork with neural adaptation successfully simulated Pettet and Gilber t's experiment of RF expansion and its reversibility induced by an ''a rtificial scotoma''. RF expansions induced by lesions were also explor ed with the model.