Neuropsychiatric effects of insular stroke.

The neuropsychiatric effects of insular damage in humans have not previously been examined. We therefore examined the neuropsychiatric impairment in seven patients with left insular stroke, six patients with right insular stroke, six patients with left hemisphere noninsular stroke, and six patients with right hemisphere noninsular stroke. Between 4 and 8 weeks after acute stroke, patients were administered a neuropsychiatric battery. Patients with right insular lesions had a greater frequency of subjective anergia and underactivity (Fisher's exact p = .002) as well as tiredness (Fisher's exact p < .002) compared with patients with non-insular lesions or left insular lesions. Subjective feelings of impaired energy or drive after right insular damage may result from disconnection between the insula and the frontal lobe or the anterior cingulate cortex, structures that have been associated with willed action and motor behavior.