Neuropsychological models of stuttering--I. Representation of sequential response mechanisms.

Male stutterers and fluent speakers were compared on index finger tapping and sequential finger tapping tasks. For both groups performance was better with the right than the left hand, and was better under conditions of visualization than under conditions of no visualization of the hand. In addition, participants in both groups showed similar variations in performance on various sequences. The pattern of results suggests that stuttering does not result from a general problem in sequencing and timing of behaviour, and is consistent with a neuropsychologial model of stuttering that would propose normal lateralization of neural mechanisms associated with sequential processing including speech.