Observations on spontaneous facial expression after focal cerebral excisions and after intracarotid injection of sodium amytal

Abstract

Ethological recording techniques were used to demonstrate that patients with unilateral frontal-lobe lesions exhibit a reduction in spontaneous facial expression, as compared to patients with unilateral parietal- or temporal-lobe lesions. There was no evidence of hemispheric asymmetry on these measures. Observation of patients during preoperative speech testing following an intracarotid injection of sodium Amytal revealed a significant reduction in spontaneous facial expressions, which outlasted any contralateral facial weakness. This result was independent of side of injection, probable lesion site, and hemisphere mediating speech. Subjective assessments of mood change following Amytal testing also showed no consistent relationship between side of injection and direction of mood change.