Modulating the Motor System by Action Observation After Stroke

• Published in: Stroke (1970) Vol. 44; no. 8; pp. 2247 - 2253
• Main Authors: Garrison, Kathleen Alice, Aziz-Zadeh, Lisa, Wong, Savio Waiho, Liew, Sook-Lei, Winstein, Carolee Joyce
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD American Heart Association, Inc 01.08.2013; Lippincott Williams & Wilkins
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Brain Mapping - instrumentation; Brain Mapping - methods; Female; Functional Laterality - physiology; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Internal Capsule - pathology; Internal Capsule - physiopathology; Magnetic Resonance Imaging - instrumentation; Magnetic Resonance Imaging - methods; Male; Medical sciences; Middle Aged; Motor Activity - physiology; Motor Cortex - pathology; Motor Cortex - physiopathology; Movement Disorders - etiology; Movement Disorders - pathology; Movement Disorders - physiopathology; Nerve Net - pathology; Nerve Net - physiopathology; Nervous system (semeiology, syndromes); Neurology; Neuropsychological Tests; Stroke - complications; Stroke - pathology; Stroke - physiopathology; Vascular diseases and vascular malformations of the nervous system; Vascular disease; Stroke; Nervous system diseases; Central nervous system disease; Plasticity; action observation; Cardiovascular disease; mirror neuron system; Rehabilitation; Cerebrovascular disease; Cerebral disorder; plasticity; rehabilitation; stroke
• ISSN: 0039-2499; 1524-4628; 1524-4628
• DOI: 10.1161/STROKEAHA.113.001105

BACKGROUND AND PURPOSE—Much recent interest surrounds the use of action observation, which is observing another individual performing a motor task, in stroke rehabilitation, to promote motor recovery by engaging similar brain regions to action execution. This may be especially useful in individuals with limited mobility. Here, we assess how cortical motor activity during action observation is affected by stroke and by stroke-related motor deficits. METHODS—We used functional MRI to compare brain activity during right and left hand action observation in right-handed nondisabled participants and participants who were right-handed before left hemisphere stroke. All participants performed the same actions after their functional MRI. RESULTS—Nondisabled participants show greater bilateral cortical motor activity when observing actions made using the left hand, whereas participants with stroke show greater ipsilesional cortical motor activity when observing actions made using the right (paretic) hand (P<0.05; corrected). For both groups, action processing is modulated by motor capabilitycortical motor activity is greater when observing the hand with lower motor scores (P<0.05; corrected). Furthermore, for stroke, the extent of ipsilesional activity correlates with lesion volume (P=0.049), in a pattern that suggests adaptive plasticity. CONCLUSIONS—We found that action observation activates specific motor plans in damaged motor circuits after stroke, and this activity is related to motor capability to perform the same actions. Cortical motor activity during action observation may be relevant to motor learning, and to motor relearning in stroke rehabilitation.