Unpleasant thoughts and anxiety induced by electrical cortical stimulation.

Emotional processing has been attracting increased attention. We herein present three patients with intractable epilepsy in whom emotional responses were elicited by electrical cortical stimulation. Negative feelings were produced in all patients; however, the content of each differed. In patient 1, the stimulation of the right anterior cingulate gyrus elicited unpleasant thoughts. In patient 2, the stimulation of the right posterior cingulate gyrus evoked anxiety. In patient 3, the stimulation of the right prefrontal cortex induced anxiety associated with a somatic sensation. Emotional responses comprise various aspects and the cortical areas responsible vary depending on each emotional aspect.