Conduction aphasia elicited by stimulation of the left posterior superior temporal gyrus.

Disruption of fascicular tracts that connect Wernicke's to Broca's areas is the classic mechanism of conduction aphasia. Later work has emphasised cortical mechanisms. To determine the distribution of language on dominant cortex, electrical cortical stimulation was performed using implanted subdural electrodes during brain mapping before epilepsy surgery. A transient, isolated deficit in repetition was elicited with stimulation of the posterior portion of the dominant superior temporal gyrus. This finding suggests that cortical dysfunction, not just white matter disruption, can induce conduction aphasia.