Psychological stress in Broca’s versus Wernicke’s aphasia

We advance the hypothesis here tha t the higher-than-average vocal p itch (F0) found fo r speech o f B roca’s-aphasics in experim ental settings is due, in p a rt, to increased psychological stress. Two experim ents w ere conducted which m an ipu ­ lated conversational constraints and the sentence form s to be produced by aphasic patients. O ur study revealed significant differences between changes in vocal pitch o f agram m atic B roca’s aphasics versus those o f W ernicke’s aphasics and norm al controls. It is suggested that the greater psychological stress experienced by the B roca’s aphasics, bu t no t by the W ernicke’s aphasics, accounts fo r these observed differences.