Habituation and sensitization of the orienting response following bilateral anterior cingulotomy.

Skin conductance response (SCR) was measured in an orienting response (OR) and habituation paradigm in 10 post-cingulotomy and age-matched control subjects. While both groups habituated, the cingulotomy patients exhibited a slower habituation rate, and greater variability across trials compared to controls. Habituation abnormalities were not associated with increased sensitization, as neither extended habituation training or dishabituation differentiated the groups. An increased frequency of spontaneous SCR activations occurred post-cingulotomy. The results suggest that the cingulate cortex influences the temporal stability of habituation. These findings are consistent with the subtle attentional dysfunction noted following cingulate damage.