6533b86dfe1ef96bd12ca814

RESEARCH PRODUCT

Unilateral medial forebrain bundle activation selectively enhances conditioned orienting head turns and ipsilateral cingulate cortex evoked field responses in cats

subject

description

Effects of a unilateral medial forebrain bundle (MFB) stimulation unconditioned stimulus (US) on conditioned head turn and bilateral cingulate cortex field potentials were studied in cats. Conditioned stimuli (CSs) of different frequences were given randomly to either ear. The CS+ was followed by the US, and the CS— was presented alone. Before conditioning most cats predominantly turned toward the ear to which the CSs were presented, whereas after conditioning the head turns were in one direction, most prominently contralateral to the US. Negative field potentials were greater in the cingulate cortex ipsilateral to the US than in the cingulate cortex contralateral to the US. Cross correlations indicated similarities between the waveforms recorded for the CS and the US within each cingulate cortex, but differences between the two sides of the cingulate cortex. It is suggested that the unilateral MFB system has brain side specific effects on conditioned orienting head turns and cingulate cortex neuronal activity.