Abstract
The study was performed to investigate the decline of intellectual functioning with aging in the elderly population. Subjects were 11, 374 (92.6%) out of 12, 280 entire elderly population (older than 65yrs) who had registered census in Yonago in March, 1980. Attending distric welfare commissioners interviewed the subjects in their own homes. Interview schedule explored physical condition, medication, social activities and others, and included an assessment of intellectual functioning by using the revised Mental Status Questionnaire (Kuhn et al.).
The number of the elderly subjects suspected to be intellectually impaired (intellectually impaired subjects) increased with aging, and were much more in women than in men (p<0.005). Correlation was observed between intellectual impairment and physical condition. Furthermore, the degree of the intellectual and physical correlation changes with aging. In the group of elderly with surviving spouse, intellectually impaired subjects were significantly less than in the subjects without spouse (p<0.005). The way of passing free time was different by sex and age groups. Though men usually engaged in activities which required some intellectual function, such as reading magazines, newspapers and etc., and volunteer activities, women comsumed free time mostly in watching TV, listening to the radio, and talk with their family members and neighbours, which did not always require use of intellect. The way of passing free time of men gradually declined to the type of women with aging. From these results, it was suggested that the senescence could be divided into 3 age groups or periods: former senescence (65-75 or 79yrs), middle senescence (80-89yrs) and later senescence (above 90yrs). This classification may be beneficial in investigational and/or practical situations in gerontology.
