Characterizing mature human intelligence - Expertise development

Results from a study of 263 male players at 48 levels of expertise in the g ame of GO, and ranging from 18 to 78 years of age, suggest a need to revise the extended theory of fluid (Gf) and crystallized (Gc) intelligence to ta ke account of continued development of intelligence throughout adulthood. T he extended theory of Gf-Gc is based on evidence that Gf, short-term appreh ension and retrieval (SAR) and cognitive speed (Gs), decline with age over adulthood. Results from a number of studies, however, suggest that within t he domains of expertise, high levels of reasoning, feats of memory and spee ded thinking similar to Gf are displayed by older adults. To explore this h ypothesis, measures of reasoning, memory and cognitive speed were construct ed within the domain of expertise related to playing the complex game of GO . Analysis of the structure of the GO-embedded measures and standard measur es of Gf (SAR and Gs) indicated a form of short-term memory - labeled exper tise working memory (EWM) - that had substantially wider span than the shor t-term working memory (STWM) of SAR. This finding is consistent with the hy pothesis that long-term working memory is built up during the course of dev eloping high levels of expertise. The results also suggest that a form of e xpertise deductive reasoning (EDR), utilizing EWM and incorporating large s tores of knowledge, is distinct from Gf. Expertise cognitive speed (ECS), h owever, was not found to be reliably distinct from the Gs factor. Analyses of cross-sectional age differences indicate an age-related decline in both EDR and EWM, but as higher levels of expertise are reached, age-related dec line does not occur. To the extent that there is continued press to advance expertise throughout adulthood, there may be improvement, decline, in the EDR and EWM forms of intelligence. (C) 2001 Elsevier Science Inc. All right s reserved.