Aging and executive function skills: an examination of a community-dwelling older adult population.

The purpose of the present study was to employ the Tower of Hanoi task to the study of possible changes in executive function skills in older adults. The study used a quasi-experimental design, with age group (i.e., young adult, young elderly, or older elderly), being the independent variable in examining performance differences between younger and older adults. Data were analyzed cross-sectionally by age group. Nineteen elderly men and women comprised two groups; nine Young Elderly with an average age of 65 years and ten Older Elderly with an average age of 75 years. Two men and ten women served as a Young Adult comparison group having an average age of 19 years. Performance on the Tower of Hanoi was measured by efficiency scores (number of trials to consecutive solutions), frequency of error types, self-correction scores (completing the goal configuration in twenty or fewer moves after committing an error precluding a "correct" solution), and error perseveration (committing the same error on two consecutive trials of a problem). Analysis of variance and chi-squared tests suggested similar executive capacities among the 9 young adult and the 8 young elderly participants as compared to their 7 older elderly peers on the 3-disk task. However, on the 4-disk task where problem complexity increased by the addition of another disk and longer move sequences, young adult participants showed superior performance on the average than either young elderly or older elderly participants. Although the present study is limited by the small sample size and the use of cross-sectional analyses to examine age differences, these findings are consistent with the hypothesis of age differences in executive function.