Structural equation model of intellectual change and continuity and predictors of intelligence in older men.

Abstract

This study examined the effects of abilities as a young adult, an engaged lifestyle, personality, age, and health on continuity and change in intellectual abilities from early to late adulthood. A battery of measures, including a verbal and nonverbal intelligence test, was given to 326 Canadian army veterans. Archival data provided World War Two enlistment scores on the same intelligence test for this sample: Results indicated relative stability of intellectual scores across 40 years, with increases in vocabulary and decreases in arithmetic, verbal analogies, and nonverbal skills. Young adult intelligence was the most important determinant of older adult performance. Predictors for verbal intelligence were consistent with an engagement model of intellectual maintenance but also indicated the importance of introversion-extraversion and age. Nonverbal intelligence in late life was predicted by young adult nonverbal scores, age, health, and introversion-extraversion.

Comparing Age Effects in Normally and Extremely Highly Educated and Intellectually Engaged 65 - 80 Year-olds: Potential Protection from Deficit Through Educational and Intellectual Activities Across the Lifespan

“…[5,6]) whereas others have not [7]. Further studies have emphasized that education has only a protective effect on certain cognitive abilities, namely the verbal abilities [7,8]. One reason for these equivocal findings may be the samples examined.…”

LIFESPAN PSYCHOLOGY: Theory and Application to Intellectual Functioning

“…Thus, adjacent time points in ontogeny tend to be more highly correlated than more distant time points. In addition, stability coefficients computed over identical lapses of time show a considerable increase in magnitude from childhood to adolescence into middle adulthood and early old age (Gold et al 1995, Hertzog & Schaie 1986, Humphreys & Davey 1988. For instance, Humphreys and Davey (1988) reported a continuous increase in one-year stability coefficients of general intelligence, with a value of .76 between the ages abilities or to everyday functioning suggests the hypothesis that performance improvements in tests of fluid intelligence primarily reflect changes in pragmatic components of performance potential, rather than improvements in the cognitive mechanics themselves.…”

Enrichment Effects on Adult Cognitive Development

“…We excluded studies that did not separate cognitive activities from other kinds of activities (e.g., Fabrigoule et al, 1995;Mackinnon et al, 2003) or that did not focus on cognitive change past midlife (e.g., Gold et al, 1995). Seven of the included studies used change in cognitive function as an outcome, and all except one (Aartsen, Smits, van Tilburg, Knipscheer, & Deeg, 2002) found that a higher level of engagement in mentally stimulating activities was associated with reduced rate of cognitive decline (Bosma et al, 2002;Hultsch et al, 1999;Schooler & Mulatu, 2001;Wilson, Scherr, Schneider, Li, & Bennett, 2007).…”

“…These types of weighting approaches have not been notably successful in increasing the predictive validity of activity scales for cognition or for cognitive change. Some initial efforts to develop mental-stimulation scales included traditional indicators of socioeconomic status like education and occupation as part of the measure (Gold et al, 1995;Gribbin, Schaie, & Parham, 1980). More recently, however, investigators have argued for separating socioeconomic status from the construct of mentally stimulating activity .…”