IS THERE LATERALIZED HEMISPHERIC CONTROL OF CARDIOVASCULAR ACTIVITY -AN AMOBARBITAL STUDY

The question of whether the influence of the cerebral hemispheres on c ardiovascular activity exhibits left/right differences is important fo r the understanding of the psychophysiology of the autonomous nervous system. Experimental results have been contradictory. One experimental procedure used is the intracarotid amobarbital test (Wada test: short anesthesia of one cerebral hemisphere). Even with this test contradic tory results have been obtained in various studies, although all invol ved relatively small of numbers of patients. Some authors have describ ed increases in heart rate following anesthesia of the left hemisphere , while others found little or no effect at all. We therefore searched for evidence of lateralization in a larger number of patients (36) wi th complex partial seizures. These patients underwent the Wada test as part of the preoperative diagnostic evaluation. In this study, inacti vation of the left or right hemisphere did not lead to significantly d ifferent effects on heart rate, or on systolic or diastolic blood pres sure.