Modulation of neuron activity in the basal forebrain of the rat related to the outcome of food-procuring movements.

Neuron activity was recorded from the basal forebrain of rats, including the mixed area of the ventral pallidum, substantia innominata, and mid part of Meynert's nucleus. The base of the forebrain was found to contain neurons (40% of all neurons recorded) which altered their activity on acquisition of a food-procuring skill in conditions of free behavior, depending on the outcome of the acquired movement reaction. The discharge frequencies of these cells increased when the animal obtained food from the feeder. When the rat was unable to procure the food, the discharge frequency of these cells either remained constant or decreased. Most of the neurons (57.1% of all neurons showing modifications) demonstrated modulation of their activity towards the end of the food-procuring movement, but before it was completed. A smaller proportion of the cells (35.7%) changed their activity after food was retrieved from the feeder.