Change of Dexterity with Age. 20

Abstract

It is a common impression that old age is accompanied by a slowing down of the voluntary processes both muscular and mental. Industrial experience and every-day observation of older adults seem clearly to indicate this change. When decrement begins, the rapidity with which it proceeds and the amount of slowing generally to be expected by the chronological ages of 60 or 70 years, are all, at present, largely matters of personal opinion. The developmental increase, for example, in motor facility from early childhood through adolescence and into adulthood, has been studied extensively. But adults in middle age and in the period of later maturity have not been conveniently available for laboratory investigations and moreover, they seem to have been actually neglected as subject material for psychological experimentation.

For the present study, a “laboratory annex” was set up in a small city and people were secured for experiment and measurement through the cooperation and solicitation of clubs, lodges, churches, and many similar agencies. An individual who came to the annex for the 2-hour series of tests was not paid but the club that sent him was paid proportionate to the person's age. The person himself knew just how much he was contributing to this club. The study includes 166 men over 50 years of age, and 169 males, younger; 302 women over 50 years and 226 women and girls younger than 50.

The total period of measurement was 2 hours in length and included several short tests and experiments. 1 , 2 The present report deals briefly with only one of these which came in the first half-hour period, a test of speed and accuracy in reaching and grasping. Two small blocks of wood were located 12 inches apart on a thin panel or lap board.