Impaired laryngeal voice production in a patient with foreign accent syndrome

We report a Japanese-speaking monolingual woman who developed foreign accent syndrome (FAS) following an infarction in the precentral and premotor cortices (Brodmann Area 6) at and around the inferior frontal sulcus. Her speech sounded Chinese or Korean to our bilingual coauthor who speaks Chinese and Japanese. Quantitative acoustic analyses of words and sentences showed that pitch (fundamental frequency variation) and intensity variances appeared lowered and fully voiced glottal pulses were reduced. These findings suggest laryngeal dysfunction that contributes to the unusual speech production in a case of FAS. This may be caused by damage to a restricted area of the motor and premotor cortices that controls laryngeal function.