Brain size and intelligence in man: A correction to Peters.

Comments on M. Peters's (see record 1992-18876-001) claim that there is no association between brain size and IQ. It is argued that this claim is incorrect. Studies showing that there is a statistically significant correlation between brain size and IQ are cited. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Abnormality of the difference and the WISC-R: Comment on Silverstein.

Discusses reactions by C. R. Reynolds (see record 1979-27697-001) and A. B. Silverstein (see PA, Vol 66:00000) to an earlier article by the present author (see record 1979-12366-001) that examined the size of abnormal differences between WISC-R subtest scaled scores and Verbal–Performance IQ scores. An error is acknowledged in the presentation of the Verbal–Performance IQ differences, and the validity of the abnormality of the difference statistic for examining subtest scaled scores is discussed. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race differences in brain size.

Replies to M. Peters's (see record 1996-14159-001) comments on Rushton's (see record 1995-17150-001) reply to a critique of his work (e.g., see record 1993-40406-001) on brain size differences among human racial groups (i.e., Mongoloids, Caucasoids, and Negroids). Rushton reports on 4 independent ways of estimating brain size, and confirms that brains of East Asians average about 17 cm–3 larger than those of Europeans, whose brains average about 80 cm–3 larger than those of Africans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"How much can we boost IQ and scholastic achievement": Addendum.

Responds to the critique by the Council for the Society for the Psychological Study of Social Issues (see record 1990-56779-001) of A. R. Jensen's article (see record 1969-09740-001) concerning the influence of heredity vs environment on IQ and scholastic achievement and suggests that the critique draws attention to Jensen's use of a social definition of race for the population tested for IQ. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

IQ gains and fluid g.

Responds to J. P. Rushton's comments (see record 2000-15413-003) on the J. R. Flynn article (see record 1999-00167-001) examining IQ gains over time. Flynn contends that factor analysis does show that inbreeding depression isolated from a cluster including fluid g, IQ gains, and Black-White differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of age-extended norms for the Wechsler Adult Intelligence Scale—Revised in patients with Alzheimer's disease.

Recent studies by R. J. Ivnik et al (see record 1993-04116-001), J. F. Malec et al (see record 1993-04120-001), and J. J. Ryan et al (see record 1991-08835-001) have provided age-extended norms for the Wechsler Adult Intelligence Scale—Revised (WAIS—R). The current study compared IQ scores based on these newer age-extended norms in 216 elderly Alzheimer's disease (AD) patients. Results showed that when the norms from Ryan et al were used, IQ scores were consistently the same as or higher than when WAIS—R manual norms were used. When the norms provided by Ivnik et al and Malec et al were used, IQ scores tended to be lower than WAIS—R manual norms for younger patients with more intellectual impairment. Results illustrate the importance of reporting the normative sample upon which IQ test scores for older adults are based and provide guidelines for selecting which set of age-extended WAIS—R norms to use with cognitively impaired elderly Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The neuroscience of education: More research is needed before application.

In reply to H. T. Epstein (see record 1991-12239-001), R. B. McCall maintains that although the recent quantitative EEG data reviewed by W. J. Hudspeth and K. H. Pribram (see record 1991-12210-001) show growth spurts conforming to Epstein's phrenoblysis theory, more research, especially longitudinal and individual difference studies, is needed before application of the theory to educational practice is warranted. Furthermore, gross indices of brain growth (e.g., head circumference) and general mental performance (e.g., mental age or IQ) do not consistently follow the theory, and research should focus on more specific measures. Finally, few data exist demonstrating that brain growth periodization relates to practical mental and educational skills and performance in the same individual children. Such research is needed before alterations in educational curricula are considered and researched. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Derived IQ estimates from the Luria-Nebraska Neuropsychological Battery in neuropsychiatric disorders.

Investigated relationships between estimates of IQ derived by S. E. McKay et al (see record 1982-04758-001) and by A. Prifitera and J. J. Ryan (see record 1982-00171-001) from the Luria-Nebraska Neuropsychological Battery, using Wechsler Adult Intelligence Scale (WAIS) IQ values as the criterion. Ss were 64 severely disturbed neuropsychiatric patients (mean age 31.75 yrs). Findings were similar to those of the previous studies regarding Luria-Nebraska correlations with standard IQ scores and question the utility of IQ estimates when relatively precise indicators of intelligence are required. Subsamples of schizophrenics and depressives are also analyzed. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race differences in brain size.

Comments on J. P. Rushton's (see record 1995-17150-001) reply to a critique of his work (e.g., see record 1993-40406-001) on biological differences among human racial groups. Rushton's categorization of racial brain weights cannot be valid because (1) comparisons of individuals drawn from the same sex and species do not allow for meaningful predictions of brain weight and (2) there is no justification for scaling brain size to body parameters. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evaluation of Wechsler Adult Intelligence Scale—Revised premorbid IQ formulas in clinical populations.

The use of demographic variables in the prediction of premorbid IQ has been noted to show some promise (R. S. Wilson et al; see record 1979-26429-001). With the revision of the Wechsler Adult Intelligence Scale (WAIS—R) and subsequent development of a regression formula for the WAIS—R (A. Barona et al; see record 1985-04035-001), some authors have suggested that continued use of the Wilson formulas is inappropriate. The present study examined the efficacy of both Wilson and Barona formulas in the prediction of concurrently obtained IQ levels in neurologically normal psychiatric (n?=?77) and brain-damaged (n?=?64) patients. The results demonstrated that neither formula differed significantly in terms of classifications of IQ range, with both formulas performing essentially at chance levels. Qualitative and quantitative differences between the formulas are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race, IQ, and rampant misrepresentations: A reply.

In L. E. Longstreth's (see record 1979-23197-001) critique of F. K. Trotman's study (see record 1978-06591-001), he attributes conclusions and interpretations to Trotman that indicate either a misunderstanding or misinterpretation on Longstreth's part or a failure in effective communication on Trotman's part. In any case, Trotman's response represents an attempt to clarify Longstreth's apparently cloudy view of the earlier Trotman work. J. L. Wolff (see record 1979-23222-001) suggested that experimenter bias operated to produce anomalies in Trotman's findings that despite similarity in socioeconomic standing, there was a difference in the intellectual home environments of Blacks and Whites, that IQ was related to home environment, and that home environment did as well as academic achievement in predicting IQ. On examination of Wolff's statements and reference citations, however, Trotman finds evidence of bias and irregularities in his critique. For example, Wolff misconstrues data, selectively either omits or includes reference citations, or statements out of context, and misrepresents previous investigations, suggesting a possibility of commentator bias. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verbal-Performance IQ discrepancies on the WISC-R: One more time.

The formula that R. J. Piotrowski (see record 1979-12366-001) used to determine the abnormality of Verbal–Performance IQ discrepancies on the WISC-R gave results that differed greatly from the actual values reported by A. S. Kaufman (see record 1977-07179-001). Since the assumption on which the formula is based, bivariate normality, is met by the WISC-R standardization data, the disparity is puzzling. It is suggested that Piotrowski erred in applying the formula not to IQs but to sums of scaled scores. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

IQ, race, and adoption.

Argues that the genetic and social variables were so confounded in S. Scarr and R. A. Weinberg's (see record 1977-07996-001) article on Black children adopted by White families that the results are consistent with virtually any theory of race differences in IQ. It is difficult to see any scientific or applied value in transracial adoption studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Delinquency and impulsivity and IQ: A reply to Block (1995).

Although J. Block's critique (see record 1995-29649-001) of the D. Lynam, T. Moffitt, and M. Stouthamer-Loeber report (see record 1993-29924-001) contains several interesting points, many of his criticisms are not valid and resulted from miscommunications, misunderstandings, and simple preferences. Specifically, the authors believe the criticisms to be the results of mistaking a single hypothesis for an organizing principle, a misunderstanding of the reported path analyses, and a simple preference for impulsivity over IQ as an explanatory construct. An attempt is made to address the misinterpretation through clarification of the predicted relations between IQ, executive dysfunction, impulsivity, and delinquency. The original path analyses are reviewed and are shown to refute not only the original self-control hypothesis (Lynam et al., 1993), as reported, but also Block's more recent version. Finally, evidence marshalled by Block to support his emphasis on impulsive personality over low IQ is argued to have inadequacies from empirical and social policy perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Some additional lessons from the Wechsler scales: A rejoinder to Kaufman and Keith.

Responds to A. Kaufman's (see record 1995-15767-001) and T. Z. Keith's (see record 1995-15768-001) comments on the article by G. M. Macmann and D. W. Barnett (see record 1995-15770-001), suggesting that discussion of their article centers not on posited questions nor conclusions, but rather on the Wechsler scales proper. Macmann and Barnett insist that Wechsler scales and other measures of general intellectual function are a costly and ineffective use of professional skills, suggesting a need for alternative models, such as assessment of cognitive variables in the context of instruction. Further, they suggest that although a general factor model may be structurally more defensible, little can be gained from the analysis of general or Full Scale IQ. It is suggested that the most promising futures for the assessment of intelligent behavior are likely to be realized through a focus on thought processes and problem-solving strategies within the context of meaningful social and instructional situations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Direct evidence for a genetic basis for black–white differences in IQ.

Claims that the American Psychological Association (APA) Task Force on Intelligence (U. Neisser et al; see record 83-26553) conclusion that there is little direct evidence to support the genetic basis for IQ differences between Blacks and Whites is in error. Studies of transracial adoption and of the racial differences in brain size are cited as examples of direct evidence for the genetic hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Commentary on profile analysis.

A plan for an ideal profile analysis system for IQ testing is sketched as a model against which to evaluate the articles on various aspects of the issue by, respectively, S. I. Pfeiffer et al (see record 2001-16379-001), C. A. Riccio and G. W. Hynd (see record 2001-16379-002), D. A. Pritchard et al (see record 2001-16379-003), J. A. Naglieri (see record 2001-16379-004), and H. C. Stanton and C. R. Reynolds (see record 2001-16379-005). Brief comments are offered on the profile analysis procedures used in each article. In general, profile analysis procedures used in these articles, although judged to be competent and acceptable in the context of contemporary research objectives, are far short of ultimate possibilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rediscovering old truths: or A word by the wise is sometimes lost.

Responds to criticisms by J. Werner et al (1977), R. C. Nichols (1977), and Q. McNemar (1977) of S. Scarr and R. A. Weinberg's (see record 1977-07996-001) article on IQ scores of Black children adopted by White families. The study's importance for demonstrating the malleability of IQ scores is emphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nonparametric effect size estimation: A reply.

Responds to criticisms by J. Krauth (see record 1984-00282-001) of the nonparametric effect size proposed by the present author and G. Andrews (see record 1982-11171-001). It is noted that Krauth's argument indicates the existence of 2 types of effect size, individual- and population-specific, that are of interest in different contexts and disciplines. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit learning differences: A question of developmental level?

A. S. Reber's (see record 1993-32264-001) proposition that the implicit learning system should demonstrate invariance of intellectual level (IQ) was examined by comparing 20 children with intellectual disability (mean mental age [MA]?=?approximately 5.8 years) with 20 intellectually gifted children (mean MA?=?approximately 12.4 years) of similar chronological age (CA; approximately 9.5 years). Implicit learning was assessed using a task involving covariation of 2 incidental cues. Explicit learning was assessed using a task of similar logical structure. Contrary to the IQ-invariance proposition, implicit learning as well as explicit learning varied with intellectual level. A secondary aim was to distinguish the contributions of CA, IQ, and MA to implicit learning. This was done by combining the samples of children in the present study with 2 samples of younger and older children of average ability from a study by M. Maybery, M. Taylor, and A. O'Brien-Malone (see record 1996-00932-001). Analyses showed that MA is critical to implicit learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)