Jeffery P. Braden

Deafness, deprivation, and IQ

Deafness as a Natural Experiment. Deafness as a Natural Experiment-Revisited. The Study of Deaf Peoples Intelligence. Evaluating the Outcomes of Deafness as a Natural Experiment. Implications of Deafness, Deprivation, and IQ for IQ Differences Between Groups. The Value of Deaf Children as a Natural Experiment for Understanding IQ Differences Between Groups. Index.

The factorial similarity of the WISC-R performance Scale in deaf and hearing samples

Abstract Wechsler Intelligence Scale for Children—Revised (WISC-R) Performance Scale metrics and subtest factor loadings, derived separately from deaf ( N = 1228) and hearing ( N = 2200) samples, are practically identical. Small mean differences are probably attributable to the higher incidence of brain damage among deaf children. In addition to demonstrating the absence of construct bias in WISC-R Performance IQ (PIQ) measurement for deaf children, the results contradict theories which propose linguistic bias as the cause of the white-black difference in Performance IQ. Spearmans hypothesis that white-black mental test differences are primarily a difference in g received significant support. The results indicate that cognition, as measured by PIQ, is virtually independent of language acquisition.

Feuerstein's Dynamic Assessment Approach A Semantic, Logical, and Empirical Critique

Since their introduction in America, the theory and techniques of Feuersteins Learning Potential Assessment Device (LPAD) and the related Instrumental Enrichment (IE) program have enjoyed substantial popularity among some educators. In our view, the reasons for this popularity are based more on philosophical considerations than on technical adequacy. In arguing this position, we critique Feuersteins theory on semantic, logical, and empirical grounds. It is concluded that evidence casting Feuersteins approach to dynamic assessment as a serious competitor to “traditional” assessment is not compelling.

An Explanation of the Superior Performance IQs Of Deaf Children of Deaf Parents

Differences in IQ between deaf children of hearing parents (HP), deaf children of deaf parents (DP) and hearing children (HC) may be due to differences in speed of information processing. The Hick paradigm was used to obtain reaction times (RT) and movement times (MT) from samples of HP (N = 31), DP (N = 31), and HC (N = 37) adolescents. Results show that DP subjects have faster RTs and MTs than HP or HC subjects (ts ≥ 2.43, ps < .01), and that greater sign language exposure is related to faster MT (r2 = .180, p < .0005). HC subjects have higher IQs than HP subjects (t = 2.66, p < .01), but DP IQs are not different from either group (ts < 1.96, NS). The results show that Performance IQs (PIQs) obscure important differences between HP, HC and DP groups. Results are discussed in light of their theoretical and educational implications.

Why Do Deaf Children Score Differently on Performance vs. Motor-Reduced Nonverbal Intelligence Tests?

Children who are deaf and hard of hearing (DC) and children with normal hearing (HC) have similar Performance IQs. However, DC score lower than HC on motor-reduced nonverbal intelligence tests (e.g., figural matrices tests). The difference between motor-reduced and motor-intensive (i.e., performance) nonverbal tests may be affected by psychomotor speed. This issue was investigated by comparing DC and HC on motor-intensive and motor-reduced nonverbal intelligence tests and on tests of psychomotor speed. Results show similar WISC-III Performance IQs for DC and HC and lower motor-reduced scores (from the Matrix Analogies Test-Short Form) for DC. This similar performance of HC and DC on an experimental motor-intensive nonverbal test, and on psychomotor speed measures, suggests that speed does not influence intelligence test results. We suspect that impulsivity, not speed per se, leads to the difference between motor-intensive and motor-reduced nonverbal test scores.

Intervention Validity of Cognitive Assessment Knowns, Unknowables, and Unknowns

The intervention validity of cognitive assessment batteries is considered within an historical context to identify what the evidence supports (knowns), what cannot be known (unknowables), and what is not yet known (unknowns). Two ways cognitive batteries could inform intervention are identified: a disordinal (i.e., aptitude-treatment interaction) model and an ordinal (i.e., g) model. Existing research provides little support for disordinal models and modest to strong support for ordinal models when applied to conditions of incomplete instruction. Limitations to what can be known (e.g., a failure to prove is not proof of failure) are identified to avoid holding intervention validity research to inappropriate evidential standards. Finally, issues that are within the realm of knowledge but for which there is currently insufficient or no evidence are identified as logical next steps toward understanding the intervention validity of cognitive assessment batteries.

WISC-R deaf norms reconsidered

Abstract Deaf norms have been published for the Wechsler Intelligence Scale for Children-Revised Performance Scale, (WISC-R PS). Argument requiring separate deaf norms are evaluated with data describing deaf and hearing childrens performances on nonverbal IQ tests. It is concluded that deaf norms are not required for deaf children. The issue of which norms a psychologist should select for scoring WISC- R PS protocols is discussed with reference to the impact that deaf and hearing norms have upon inter- and intraindividual comparisons.

The Structure of Nonverbal Intelligence in Deaf and Hearing Subjects.

Factors extracted from the normative samples of the Wechsler Intelligence Scale for Children Performance Scale (WISC PS; Wechsler, 1949), Wechsler Intelligence Scale for Children-Revised Performance Scale (WISC-R PS; Wechsler, 1974) and Hiskey Nebraska Test of Learning Aptitude (HNTLA; Hiskey, 1966) are compared to factors emerging from deaf normative samples on these nonverbal intelligence tests (WISC N = 300; WISC-R N = 1,228; HNTLA N = 550, N = 529). All data sets yield a first principal factor which is virtually identical (rc ≥ .986) for deaf and hearing samples. The similarity of first principal factors supports arguments that deaf and hearing people do not exhibit major qualitative differences in nonverbal intellectual structure, and contradicts suggestions that mental abilities develop more independently in deaf children than in hearing children.

Hard-of-Hearing and Deaf Clients: Using the WISC-IV with Clients Who Are Hard-of-Hearing or Deaf

Publisher Summary This chapter intends to help clinicians understand the unique issues that arise when they use the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV) with deaf or hard-of-hearing children. The primary concern confronting examiners who are charged with assessing the intelligence of deaf and hard-of-hearing children is differentially diagnosing intellectual deficits from experiential deficits. Deaf and hard-of-hearing children vary substantially in their means of communication. Slightly more than half (54.9%) of the deaf and hard-of-hearing students in U.S. schools receive instruction using formal sign systems, and slightly less than half (44.5%) are taught exclusively via speech. Examiners must identify relevant communication needs and ensure they accommodate those needs when communicating with and assessing deaf or hard-of-hearing children who rely primarily or exclusively on spoken communication. Given the complexity of these issues, examiners should consider carefully whether they have the competence for assessing deaf and hard-of-hearing children. Research on tests of intelligence using deaf and hard-of-hearing examinees yields a number of findings that examiners should consider when interpreting test scores.

Fact or artifact? An empirical test of Spearman's Hypothesis

The possibility that Spearmans Hypothesis is a statistical artifact is tested with studies of deaf childrens intelligence. Six published and unpublished sources yielded 37 instances in which the magnitude of deaf-hearing differences, and the g loading of the test for deaf children, could be determined on intelligence tests. The magnitude of differences between deaf and normal-hearing children are negatively correlated with g loadings (r = −.14, NS), and are significantly different from positive correlations reported for black-white differences (zs > 2.51, ps < .01). Post hoc analyses show the lack of positive relationship between deaf-hearing differences and g loadings is consistent across psychometric and subject samples. The results clearly refute Schonemanns (1985) proposal that the positive relationship between black-white differences and g loadings is a statistical artifact, and the results provide evidence of divergent validity for Spearmans Hypothesis.