Differences on six Horn abilities for 14 age groups between 15–16 and 75–94 years.

Abstract

Six abilities derived from Horn's fluid (Gf) and crystallized (Gc) theory were investigated for 1,193 individuals (607 men and 586 women), aged 15-94 years and approximately representative of the U.S. population on ethnic, socioeconomic, and geographic variables. Age differences on the Horn abilities were analyzed for separate age groups across this wide age span, both with and without control for education, using multivariate analysis of variance and multiple regression analysis. Results supported Horn's classification of crystallized and quantitative as maintained abilities and of fluid and broad visualization as vulnerable abilities. Short-term acquisition and retrieval, usually interpreted as vulnerable, was maintained through the 60s for the present sample. The patterns of age differences on long-term retrieval tasks were a function of the type of material to be stored. Horn (1989) and his colleagues (Horn, Donaldson, & Engstrom, 1981; Horn & Hofer, 1992) have conducted a considerable body of research on the structure of human abilities. They have identified about eight or nine factors that now define fluid (Gf) and crystallized (Gc) theory. The current theory is an expansion and refinement of the original Horn and Cattell (1966, 1967) theory that stressed the distinction between crystallized, acculturated knowledge and novel, fluid problem solving. The research that has accompanied the elucidation of the expanded Gf-Gc theory has continued to emphasize age differences on the specific ability factors, a topic of interest to the theorists from the initial development of the Gf and Gc constructs

Seven questions about the WAIS-III regarding differences in abilities across the 16 to 89 year life span.

“…The present study supports the vulnerable nature of Gv and suggests that the age-by-age pattern for Gv and Gf are extremely similar. That same finding was reported in a study of purported Gf and Gv subtests included in the Kaufman Short Neuropsychological Assessment Procedure (K-SNAP; Kaufman & Kaufman, 1994), namely Gestalt Closure, a well-known measure of Gv, and Four-Letter Words, a novel test of fluid reasoning and planning ability (Kaufman, Kaufman, Chen, & Kaufman, 1996). For 1,193 individuals, ages 15-94 years, education-adjusted mean scores demonstrated extreme vulnerability across this wide age range and the age patterns were highly similar for Gv and Gf abilities; adjusted means peaked at 106-109 in late adolescence and young adulthood, decreased to 99-100 at ages 50-54, and dropped to 82-83 at ages 75-94.…”

The Precipitous Decline in Reasoning and Other Key Abilities with Age and Its Implications for Federal Judges

“…Gq is “ the breadth and depth of declarative and procedural knowledge related to mathematics … For a complex society to function, most adults must have mastered core numeracy skills… To provide public services and to guide public policy, a sizeable proportion of the population must also understand the basics of algebra, geometry, and statistics” ( Schneider and McGrew 2018, p. 123, italics in original ). A test of Gq , usually found to be a vulnerable ability, has been studied extensively by Schaie ( 2012 ) and other researchers e.g., ( Kaufman et al 1996 ; Kaufman et al 2008 ; Kaufman et al 2009 ; McArdle et al 2002 ); Gq should be considered for the new test battery.…”

Test Reviews : Kaufman, A. S., & Kaufman, N. L. (1993). Kaufman Adolescent and Adult Intelligence Test (KAIT). Circle Pines, MN: American Guidance Service

“…It is likely that an MA-Glr factor did not emerge in the previously mentioned cross-battery analyses because not enough markers of this construct were included (i.e., the construct was underrepresented in previous analyses; see Kaufman, Kaufman, Chen, & Kaufman, 1996, for support of this Glr interpretation of the KAIT's delayed-recall subtests). It is likely that an MA-Glr factor did not emerge in the previously mentioned cross-battery analyses because not enough markers of this construct were included (i.e., the construct was underrepresented in previous analyses; see Kaufman, Kaufman, Chen, & Kaufman, 1996, for support of this Glr interpretation of the KAIT's delayed-recall subtests).…”

“…In contrast to Kaufman and colleagues' cross-battery investigations, the Rebus Learning, Rebus Delayed Recall, and Auditory Delayed Recall subtests in Flanagan and McGrew's (in press) study loaded on the Associative Memory (MA-Glr) factor with the WJ-R MA markers. It is likely that an MA-Glr factor did not emerge in the previously mentioned cross-battery analyses because not enough markers of this construct were included (i.e., the construct was underrepresented in previous analyses; see Kaufman, Kaufman, Chen, & Kaufman, 1996, for support of this Glr interpretation of the KAIT's delayed-recall subtests). It should be noted that Auditory Delayed Recall also loaded on the Gc factor.…”