Emotionally evoked changes in cerebral hemodynamics measured by transcranial Doppler sonography

The cerebral representation of emotions has previously been investigated by the study of patients with local brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques such as positron-emission tomography or magnetic resonance imaging measuring local cerebral blood flow. We investigated the mean flow velocity (FVmean) in the middle cerebral artery (MCA) by transcranial Doppler sonography during emotional stimulation with video scenes in 24 healthy test persons. The videos consisted of an erotic scene and a violent scene shown in contrast to a calming scene. Blood pressure, heart rate, and breathing frequency were monitored continuously by noninvasive measurement. FVmean increased during the erotic scene to 108.5+/-11.9% (P < 0.05) of the baseline value in the right MCA and to 109.0+/-10.6% (n.s.) in the left MCA. During the violent scene FVmean reached 109.0+/-8.7% (P < 0.05) on the right side and 108.1+/-13.0% (n.s.) on the left side. The FVmean time course showed a close relationship to the video sequence. During scenes involving great tension FVmean showed a plateaulike state and peaked during sudden actions. Blood pressure, heart rate, and respiratory rate showed no significant changes. However, we observed a tendency towards lower heart rates (lowest value 94.5+/-13.6%) during the erotic scene and two peaks (103.2+/-13.3%, 104.8+/-16.8%) coinciding with sudden violent actions. The significant increase in FVmean in the right MCA supports the theory of a right hemisphere dominance for the processing of emotions.