Apraxia is an impairment in the ability to pantomime or imitate gestures usually caused by a stroke more frequently to the left than the right hemisphere. Due to the complex nature of apraxia, disruptions to a number of different cognitive and motor processes have been proposed to underly this disorder. In order to examine disruptions to these processes the participation of a special population of people who have suffered a stroke has been enlisted. The role of memory has been particularly well elucidated in studies of this special population, as patients with left hemisphere damage exhibit a particular deficit in performing gestures from memory. In this paper, through use of a model depicting the stages involved in gestural production, the processes that might be affected at each stage by left hemisphere damage are examined. The implications of the “cognitive neuropsychology” approach for incorporating special populations into research in the movement sciences are considered.
Eric A. Roy, Liana Brown, and Tammi Winchester are with the Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada N2L 3G1. Paula Square is with the Graduate Department of Speech Pathology and Sandra Black is with the Department of Medicine, University of Toronto, Toronto, ON, Canada M5S 1A1. Craig Hall is with the Faculty of Kinesiology, University of Western Ontario, London, ON, Canada N6A 3K7.