Stroke is the leading cause of death and disability and has the largest socioeconomic burden of any disease in Canada. Survivors are frequently left with long-term disabilities that diminish their autonomy and quality of life and result in the need for chronic care. As such, there is an urgent need for therapies that improve stroke recovery, as well as accurate and quantitative tools to measure function. Non-human primates closely resemble humans in neuroanatomy and upper limb function, and may be crucial in bridging the translational gap for testing stroke therapies. Cynomolgus macaques were trained on a visually guided reaching task on the Kinesiological Instrument for Normal and Altered Reaching Movements (KINARM). We then induced strokes in these animals by transiently occluding the medial cerebral artery for 90 minutes and assessed their motor performance on the same reaching task throughout recovery. During the weeks following stroke, we noted recovery of function that plateaued by two months post-stroke. In comparing performance in this chronic stroke state to performance pre-stroke, we found that hand movements in the task became slower, less accurate, and less stereotyped. Taken together, these studies highlight specific sensorimotor deficits in visually guided reaching movements following stroke and validate the use of robotic assessment tools in identifying and quantifying such deficits.

MECHANISMS OF MOTOR RECOVERY IN A NON-HUMAN PRIMATE MODEL OF CHRONIC STROKE