Comparing the Immediate Effect of Auditory and Visual Mental Imagery on Reaching and Grasping Task among Sub acute Stroke Patients

The term cereberovascular accident (CVA) is used interchangeably with stroke to refer to the cereberovascular or hemorrhagic lesions. According to World Health Organization ‘stroke is defined as rapidly developed clinical sign of a focal disturbance of cerebral functional of presumed vascular origin and of more than 24 hrs duration’. Included within this definition are most cases of cerebral infarction, cerebral hemorrhage and subarachnoid hemorrhage but deliberately excluded are those cases in which recovery occurs within 24 hrs¹. The degree of recovery from hemiperesis, however, varies considerably, and >50% of patients are left with residual motor deficits². Upper-limb hemiperesis (ULH) is one of the most debilitating effects of stroke, and it is the primary impairment underlying functional disability following stroke^3–5. Stroke induced affected arm non use often causes greater motor disability to be exhibited than that which actually exists and this can produce affected limb bone and muscular atrophy⁶. Visual imagery is the ability to retain an accurate, detailed visual image of a complex scene or pattern (sometimes popularly known as photographic memory) or the ability, possessed by a minority of people, to ‘see’ an image that is an exact copy of the original sensory experience⁷. Whereas, auditory imagery is the subjective experience of hearing in the absence of auditory stimulation. In this study we are comparing the effects of both type of mental imagery i.e. visual and auditory. Purpose of the study was to determine the relative efficacy of auditory and visual mental imagery to increase upper limb function among sub acute stroke patients.

30 subjects of age group 50- 70 years were selected as per inclusion and exclusion criteria. Quality of movement & Amount of use was recorded through motor activity log.

All 3 groups showed improvement. Kruskal Wallis test scores showed significant differences in all three groups where QOM scores in pretests were.47 and.21 ans were 0.11 and 0.05 in posttests. Also these scores showed that video imagery proves better as compared to auditory imagery in enhancing the QOM in an individual as the test scores were 20.40, 17.85, and 8.25 respectively in the post test.

This study concludes that visual mental imagery appears to be a promising rehabilitaion protocol for improving affected upper limb motor function in stroke patients as compared to auditory mental imagery.