Abstract

Background: The normal process of aging involves decline in cognitive and sensorimotor functions that affect performance of activities of daily living. Cognitive decline & motor system decline can coexist in elderly. Previous studies have indicated that cognitive factors in addition to peripheral changes are involved in dexterity decline. However, these studies have used either global measures of cognition or a selective domain of executive function. The purpose of the present study is to further explore this relationship and evaluate which specific domain/s of executive function is/are associated with manual dexterity in older adults. Design: Cross-sectional, observational. Setting: Physiotherapy department in a tertiary care center, Mumbai, India. Participants: Community-dwelling older adults between 65-84 years of age (n= 35). Main Outcome Measures: Executive functions were assessed for various domains using neuropsychological tests viz. TMT A & B (visuomotor tracking and mental flexibility, psychomotor speed), Stroop test (inhibitory process, selective control), Digit span forward & backward test (working memory), Clock drawing test (planning and visuoconstructive skills) and Verbal fluency test (semantic processing). Manual dexterity was assessed using Purdue pegboard test (assembly task). Results: The mean (± SD) age of the participants (n=35) was 71.77 (± 5.88) years and they were predominantly male (63%). Analysis (using Spearman test, p < 0.05) showed a significant correlation of Purdue pegboard test with TMT A (rs =-0.5496), TMT B (rs = -0.6128), Stroop test (rs =-0.4327), Clock drawing test (rs =-0.5432) & Verbal fluency (rs =0.5503). No significant correlation was found with the Digit span test. Conclusion: Executive function (all the domains, except working memory) is significantly associated with manual dexterity in community-dwelling older adults aged 65- 84 years. These findings suggest that integration of complex cognitive and sensory mechanisms constitutes a crucial component of hand motor function in this population. This study provides a reasonable basis for implementing cognitive intervention strategies for manual dexterity impairment and new insights for hand rehabilitation in community-dwelling older adults.