Initiation, Inhibition and Strategy Generation Across the Healthy Adult Lifespan.

ABSTRACT

OBJECTIVE: Executive functions are crucial for adaptive behavior in novel contexts. In healthy aging, these abilities are more sensitive to dysfunction than other cognitive abilities. The effect of aging on initiation, inhibition, and strategy use was investigated via performance on the Hayling Sentence Completion Test. METHOD: The standard Hayling Test and baseline cognitive tests were administered to healthy adults (N = 344), aged 18-89 years (cross-sectional study). Bivariate Pearson's correlations, partial correlations, and regression analyses were used to assess the impact of aging on the components of the Hayling Test. RESULTS: There were significant positive correlations between age and response time for both Initiation and Suppression, and the number of Suppression Errors. Further, older age was negatively associated with strategy use. These findings remained significant after controlling for demographic factors such as education and crystallized intelligence and other cognitive functions sensitive to aging such as fluid intelligence, attention, working memory and semantic and phonemic word fluency. CONCLUSIONS: This study provides clarification of the effect of age on the processes of initiation, inhibition, and strategy generation across the adult lifespan. The focus and analysis of strategy on the Hayling Test provides clinicians with an additional and valuable measure of executive functioning. That is, it provides insight into how older adults may be able to compensate for decline in these processes, and thus maximize quality of life and independence.