[New electrophysiologic data on localizing visual representation in the limbic area of the neocortex]

In the limbic part of the rat neocortex, afferents from the retino-geniculo-cortical and retino-tecto-thalamo-cortical visual subsystems converge to the area 29. A specific feature of the area 29 responses to stimulation of thalamic visual nuclei (the LGB and the postero-lateral nucleus) involves gradualness of their appearance during rhythmic stimulation. The responses have an initial negative phase, are resistant against nembutal, have a short and stable latency, their neuronal reaction being phasic in nature and showing dependence on physical parameters of stimulation. These intermediate type reactions possess features of both specific and unspecific responses of the neocortex which seems to be characteristic of the area 29 function.