AUSTRALID MENTAL DEVELOPMENT AND GERIATRIC DECLINE

Abstract

Stdmnznry.-Truly definitive studies are very rare in science. The present writers use the analogy of an uncompleted picture puzzle, which still may have meaning even if some pieces are missing. One area as yet unfilled concerns the course of early development and geriatric decline in primitive peoples. Yet this work might well be crucial as regards the significance of racial or ethnic differences. This article describes certain difficulties inherent in the task. Among them is finding sufficient numbers of elderly aborigines, selection of an acceptable measure, and the scoring of test results when obtained. The evidence herein presented indicates that among Australids the fourth decade of life (31 to 40 yr.) is the period of initial onset of deteriorative changes. Supplementary data regarding individuals between 40 and 70 yr. of age are needed before the tempo of decline can be determined. Nevertheless, if early appearance and more rapid decline is the rule, then this may go far to explain the simple cultural level attained by these people. Restricted productivity of inventive devices could be a factor, and of this ability the Porteus Maze seems to be a reliable index. At the other end of the age-scale, aboriginal children attending school at Palm Island, Northeast Queensland, were tested. Less difference between these Ss and groups in other, more sophisticated situations was found. Their Maze scores were surprisingly high. There was not much difference between the means of partaborigines and reputed full-bloods. But it is pointed out that success in the Maze is related not to all-round intelligence but rather to practical abilities. Moreover, when these performances were subjected to qualitative scoring, which has been shown to reflect delinquent trends in our society, the early adolescent group of Palm islanders had average Q scores almost exactly midway between those of delinquents and non-delinquents. A similar situation was found by Porteus and Gregor (1963) for Central Australian aborigines resident at the Finke River Mission at Hermannsburg. This may have a bearing on the success or otherwise of their assimilation with the white community. The better standing of the Palm Island group is attributed to their younger status and to much more direct educational and social supervision. As regards male geriatric decline, our data show that the group aged over 70 yr. (N = 23) could only score 7.04 yr., but a group of 11 cases between 41 and 60 yr. rose to 10.15 yr., or 3 yr. higher. Comparative data from a 1962 study indicated no changes up to 40 yr. of age, but a decline from 11.5 to 10.5 yr. on the Maze Test occurs in the following decade.