Spatial distribution of activity of the neurons of the visual cortex during stimulation with a flash of diffused light.

At different stages in the development of the response to a flash of diffused light, groupings of excited neurons in field 17 of the guinea pig continue to occur within the same cortical microzones. These zones are separated from neighboring microzones by narrow inhibition zones. The ensembles of cells participating in excitation form columns tapering with depth. The groupings of excited cells noted during a silent break indicates a grouping of inhibitory neurons. Three subgroups are distinguished within the ensembles according to the average dynamics of their impulse activity; the groups are reciprocally interrelated. One of the subgroups is in the lower layers of the cortex. This subgroup is characterized by stably localized foci of maximal activity; their dynamics, apparently reflecting groupings of corticofugal neurons, are sharply distinguished from the subgroups of the middle layers. The ensembles under investigation are considered to be one of the forms of activity of the structural-morphological units in the cortex.