| Abstract: | Smiling as an index of cognitive mastery was examined in a study of seven infants clinically diagnosed as having Down's syndrome. The subjects were administered the Uzgiris-Hunt scales of infant psychological development on five occasions over a four month period of time, and their smiling responses to their successful and unsuccessful completion of the items administered were coded. Two hypothesis derived from J. McVicker Hunt's theory of intrinsic motivation were tested: (a) sense of pleasure derived from successful solutions would be greater than to tasks not solved correctly, and (b) sense of pleasure to optimally challenging tasks would be greater than to tasks which could be solved easily. The findings provided support for the first but not the second prediction. The results are interpreted in terms of similarities and differences found in the present and previous investigations, and the implications of the findings are discussed. |
