Abstract
In thirty-three (54%) out of 61 patients with spontaneously occuring complex partial seizures of temporal lobe origin documented on CCTV/EEG by means of bilaterally implanted intracranial depth/subdural electrodes, 43 ictal vocalization or verbalization were disclosed. They were divided into vocalization (23), linguistically appropriate speech (11), and inappropriate speech (9). Vocalization and verbalization were likely to occurr in seizures arising either from language-dominant or from nondominant hemispheres. In two-thirds of the cases, seizure discharge activities were observed bilaterally at the time when the speech occurred. Most of the seizure discharges arising from temporal lobe of dominant side spreaded to the contralateral hemisphere when vocalization, though less often in the form of appropriate speech, occurred, to the contrary, the discharges arising from temporal lobe of nondominant side spreaded to the dominant side temporal lobe when inappropriate speech occurred. No demographic factors were found which favored the occurrence of ictal vocalization or verbalization. We concluded that either vocalization or verbalization as an ictal event does not help predict the location of seizure onset, but may reflect function of the cerebral dominance interfered by the spread of seizure discharges. We also stressed the possible role of the extratemporal structures such as supplementary motor area and/or cingulate gyrus in both vocalization and verbalization.
