Plastic changes of unit activity induced by tactile stimuli followed by electrical stimulation of single hippocampal and reticular neurons

Abstract

The reactions of 127 single neurons to combinations of tactile stimulation, and electrical stimulation through the recording micro-electrode, were recorded in the hippocampus and reticular formation of 68 rats. In those neurons in which a classical conditioning paradigm of tactile and electrical stimulations was used, 12 per cent of the hippocampal cells and 8 per cent of the reticular formation cells formed plastic changes in reactivity to the tactile stimulation. These findings are in good agreement with earlier results using an acoustic CS. In those reticular neurons in which the tactile stimulus was applied on a background of continuous polarization 19 per cent showed a modification of reactivity to the tactile stimulus. Sensitization and other alternatives are discussed in relation to these results.