Dichotic monitoring as a test of hemispheric dominance in cases of epilepsy.

The predictive validity and reliability of a dichotic monitoring test of speech lateralization was assessed in four cases of epilepsy. Speech dominance was subsequently determined by both the intracarotid amylobarbitone test and the results of neurosurgery. On the patients tested, faster reaction times (RT) to target words in one ear was an accurate and consistent indication of contralateral hemispheric dominance. The variability in performance associated with epileptic disorders was reflected in the inconsistent ear differences obtained using target detection rates, however the RT measures yielded stable ear differences.