SPATIAL-ORGANIZATION OF RECEPTIVE-FIELDS OF CATS - HIPPOCAMPAL VISUALLY DRIVEN NEURONS

According to the spatial configurations of receptive fields two broad groups of neurones in dorsal hippocampal region (HR) were distinguishe d. The receptive field borders of 22 cells have regular (R) smooth con tours (squares or rectangles), casually with a horizontally oriented l ongitudinal axis. The second group was composed of neurones (20 cells) with irregular (IR) configurations of receptive fields. Some neurones (16 cells) of this group had relatively simple spatial configurations of receptive fields and 4 neurones had receptive fields with more int ricate spatial configurations which formed complex geometrical shapes in the visual field. The exploration of the distribution of response p roperties a to stationary flashing spot over the RF surface revealed t hat the majority of cells with regular receptive fields have heterogen eous stationary structure with ON, ON-OFF and OFF subregions sequentia lly located in the receptive field, and these neurones, as a rule, wer e direction-sensitive. The neurones with irregular receptive fields, o n the other hand, had a rather homogeneous structure of RFs when teste d by a stationary flashing spot and only four neurones of 20 investiga ted were directionally sensitive.