Aging and performance on some cognitive and psychomotor tasks
Creators: name: Friedt, Marguerite
Publisher: name: University of British Columbia
Year: 2011

description: The main purpose of this study was to examine some of the effects of normal aging on test performance where: (a) short-term memory was an important component (b) intellectual and psychomotor speed was involved. Six related hypotheses were investigated using a group of tests administered individually to each subject during a one hour testing period. The degree and nature of change in test performance was studied on a sample of 120 volunteers aged eleven to seventy. There were ten males and ten females in each decade group, and subjects were assigned at random to different treatments where this was necessary to avoid practice effects. Hebb's (1949, 1961) theory was used as a frame of reference, augmented by the theories of Welford (1958) and of Broadbent (1958, 1963). An attempt was made to evaluate the Maturation Degeneration Hypothesis on the basis of the experimental results, with reference to Dorken's (1958) contention that the normal effects of aging on intellectual function have often been over-emphasized. The tests were grouped into two general classes: those which measured speed of performance on familiar tasks; and those which examined the relationship between aging and interference on memory with regard to both familiar and unfamiliar tasks. The experimental results showed a tendency to follow the pattern predicted by the Maturation Degeneration Hypothesis, although analysis failed to show a statistically significant relationship between aging and performance on all of the tests. Nevertheless, it is reasonable to conclude, on the basis of these experimental results that: (l) The theoretical formulations of Hebb, Welford and Broadbent may be useful in explaining some changes in mental function which accompany advancing age. (2) Speed of performance decreases from the twenties to the sixties, although this decline is not statistically significant for all tasks involving rote repetition of familiar everyday verbal material. (3) Aging appears to have less effect than commonly supposed, on the amount of verbal and numerical material which can be grasped and retained over a short period of time under the conditions used here. (4) There was no significant relationship between aging and performance on a verbal learning test provided the recognition method was used to test retention. However, there was a significant decrease with aging and performance when tested by recall. (5) There is a relationship between aging and the effects of interference, although this relationship was found not to be statistically significant in the tasks used here. (6) Performance on a test requiring extensive reorganization of pre-existing habits declined significantly with aging which suggests that learning difficulty in older people is partly a function of the amount of interference from old habits. By and large the results were in line with expectation and tended to support Dorken's view that changes in cognitive functions with age, and in the absence of cerebral pathology, are less drastic than is commonly held to be the case.