THE RELATIONSHIP OF CORTISOL TO PRACTICE-RELATED GAINS IN INTELLIGENCE AMONG OLDER PERSONS

Based on data collected fi om two separate samples of older adults, th e present study explored the role of cortisol in mediating practice-re lated gains in fluid intelligence (Gf) among older adults. Analyses ac ross samples involved treatment group participants who received stress inoculation training in order to reduce anxiety concerning intellectu al performance; waiting list control group participants did not receiv e training until the experiment(s) were completed. Practice effects we re examined for both groups. In Study 1, the sample consisted of a het erogeneous (re: concerns about intellectual performance) group of olde r adults, and Study 2 participants were older adults who self-reported as being at least moderately anxious or concerned about intellectual performance declines. The two samples differed on health (p < .01), wi th Study 2 participants being healthier las determined via self-report ). Results indicated that practice, but not training, effects were evi dent for measures of crystallized ability (Gc) and Gf across both stud ies. The data also suggested that cortisol mediation was different for the two samples in that it was negatively correlated with Gf in the f irst sample, and, though not significant, positively correlated with G f in the second. The same directional relationships were evident for t he measure of Gc. Comparisons between studies regarding correlations b etween cortisol and practice-related gains in performance were signifi cant for Gf (p < .01) and approached significance for Gc (p < .07). Th ese data seem to suggest that for same older persons, higher levels of cortisol interfere with the effects of practice on Gf performance, wh ile for others, higher cortisol facilitates such gains in performance.