Some evidence of bilateral speech representation in sinistrals

The information provided by pre and post-operative surface EEG, cortical EEG, cortical stimulation, intracarotid barbiturization, psychometric testing and ictal semiology are integrated in order to define the speech regions. The three patients described are predominantly left handed and left cerebral hemisphere dominant, all with right hemisphere epilepsy. All are considered to have bi-lateral speech representation to account for dysphasia during cortical stimulation in all three and ictal or post ictal dysphasia in the first two and post-operative dysphasia in the first and third. Some of the evidence that supports the possibility of bi-lateral speech representation is discussed.