Study of the action of the nucleus accumbens septi electrical stimulation upon the unitary activity of the amygdaloid complex of waking cats.

The extracellular activity of the amygdaloid cells and the action of the NAS stimulation upon them were studied in unanesthetized, non-paralized, waking cats. The neurons were classified according to their responsiveness to olfactory, auditive, visual and behavioural stimuli, and then, the action of the NAS electrical stimulation upon the spontaneous activity of the previously classified cells was studied. The number of cells responding to visual stimuli (projected spot of light, movement) was found to be higher than in previous works. On the other hand, some of the cells activated by behavioural stimulation (presence of rat) behave in a complex manner by changing the characteristics of the response upon modification of its distance from the rat. However the majority of the recorded neurons failed to respond to any of the tested natural stimuli. The existence of rather extensive zones in the amygdaloid complex without spontaneous activity as well as the small number of cells showing modifications of the rate of firing induced by NAS electrical stimulation was remarkable.