Jeffrey W. Gray

A comparison between intelligence and neuropsychological functioning

Abstract The overlap of the Wechsler Intelligence Scale for Children—Revised (WISC-R) and the Halstead-Reitan Neuropsychological Battery (HRNB) was investigated in light of their use in diagnosing childrens learning problems. Scores for 1,181 children on the WISC-R and the HRNB were related using a canonical correlational analysis. One significant correlation emerged, R c =.64. Further analyses indicated that some 10% of the variance of both the HRNB and the WISC-R were redundant. The primary source of overlap between measures was attributed to cognitive functions. In an effort to explore the constructs for both measures, data from the WISC-R and the HRNB were submitted to a factor analysis. Six factors emerged, three of which corresponded closely to those usually reported for the WISC-R. The implications for assessing childrens learning disabilities are discussed.

Construct validity of the PPVT with neuropsychological, intellectual, and achievement measures

The present investigation examined the construct validity of the Peabody Picture Vocabulary Test (PPVT) with learning-disabled children. The Wechsler Intelligence Scale for Children-Revised (WISC-R), the Wide Range Achievement Test, and the Halstead-Reitan Neuropsychological Battery were administered to 934 learning-disabled children. Seven factors were isolated on the basis of a principal-components factor analysis and Varimax rotation. PPVT scores were found to load on a factor similar to what has been labeled verbal comprehension on the WISC-R with little secondary loadings on any of the remaining six factors. Implications for practitioners and further research were discussed.

The effect of modality on long-term recognition memory

Two experiments examined the effects of visual and auditory modes of input on long-term memory. In Experiment 1, 40 subjects learned a 40-word list presented in a blocked or random fashion. In the blocked conditions learners were presented half the nouns in one modality followed by the remaining 20 words in the other modality (See-Hear or Hear-See). Subjects in random conditions also received half the list in each modality, but the presentation was random (Mixed or Mixed Reverse). Following a 6-min delay, subjects completed an 80-item visual recognition test. Analysis of these data showed significantly (p < .05) greater recognition of words presented visually than those presented auditorily. Experiment 2 was designed to test the hypothesis that learners may visualize a “literal copy” of the stimulus item by controlling for the extent to which the recognition measure offered a visual cue. Two groups of 40 subjects were examined using the same procedure used in Experiment 1, with the exception that one group received a visual recognition test while the other was tested auditorily. These data showed that the lack of a visual cue hindered the recognition of visually presented words, while it had little effect on stimuli presented auditorily. The results of these experiments were interpreted as support for the hypothesis that physical characteristics of a stimulus may persist in memory well beyond immediate memory intervals. Subjects were seen to make modality-specific decisions by testing long-term memory for the presence or absence of a visual memory trace.

Assessment of perinatal risk factors

The test-retest stability of the Maternal Perinatal Scale (MPS) was examined for a random sample of 41 mothers. The stability of items over a two-day period ranged from 1.00 to .85 (r) for items with an underlying normal distribution and from 1.00 to .86 (Cramers V or Phi coefficient) for nominal items. Moreover, 90% of the coefficients exceeded .90. Intercorrelations between specific information assessed by the items were consistent with clinical obstetric and research evidence. The results were interpreted as lending support to the clinical and research potential of a systematic self-report format in the assessment of perinatal histories.

The Incremental Validity of the Halstead-Reitan Neuropsychological Battery in Predicting Achievement for Learning-Disabled Children

This study examined the incremental validity of the Halstead-Reitan Neuropsychological Battery for older children (HRNB) over the Wechsler Intelligence Scale for Children-Revised in predicting scores on the Wide Range Achievement Test (WRAT) for 989 children referred for learning difficulties. A substantial increase (16 to 30%) in the variability accounted for in school achievement resulted with the addition of the HRNB tests to information obtained from the WISC-R. Specific tests of the HRNB were discussed in light of their unique contribution to the prediction of each of the three WRAT subtests (Reading, Spelling, and Mathematics).

Neuropsychological Aspects of Primary Affective Depression

This study compared the neuropsychological functioning of 50 primary affective depressives and a like number of normals on the complete Halstead-Reitan Neuropsychological Battery. Psychiatric diagnosis was based on Research Diagnostic Criteria. Comparison of the Wechsler subtests seen to measure right and left hemispheric functioning revealed a relative deficit for depressives on those tasks shown to be most sensitive to right hemispheric functioning. Profile similarities (rp) between groups on the combined Wechsler and Halstead-Reitan variables indicated normal similarity on left hemispheric tests and a significant dissimilarity on right hemispheric measures. Impairment ratings for each Halstead-Reitan measure indicated that depressives were significantly impaired when compared to normals on right hemispheric tasks, while they were within normal limits and did not differ from normals on left hemisphere impairment ratings. The potential of neuropsychological measures as diagnostic markers of psychiatric illness was examined.

Mothers' self-reports of perinatal information as predictors of school achievement

Abstract This study examined the relationship between perinatal information and school achievement for children with learning problems. Multiple regression analyses showed that perinatal information alone and in combination with Wechsler Intelligence Scale for Children-Revised subtests accounted for a significant amount of the variability in the three achievement dimensions of the Wide Range Achievement Test. Moreover, perinatal variables in concert with intellectual information were highly related to childrens overall school achievement. The results were interpreted as lending support to a multivariate link between perinatal events and school achievement as well as the utility of considering structured maternal reports of perinatal information in concert with measures routinely administered by psychologists in the schools in the prediction of school functioning.

Item identification speed and memory span performance in learning disabled children

Abstract Previous studies have found that slower naming latencies correlate with the memory span difficulties of learning disabled (LD) children. The current study attempted to further clarify the relationship between speed and span by directly examining whether slower identification of item information is the source of span difficulties in LD children. Forty-eight 6th-grade boys participated in the study, 24 LD and 24 non-LD. The method involved pretesting each subject to obtain mean naming latencies for each of eight classes of stimuli. The experimental procedure then presented each subject with two memory span tasks: one using stimuli that had produced comparable group naming latencies, and the other with a stimulus class that had produced significant group differences in naming speed. The results indicated that span performance varied directly with naming speed. Results were discussed within the working memory framework of A. D. Baddeley and G. Hitch (1974) , in The psychology of learning and memory (Vol. 8), New York: Academic Press).

Assessing the Commonality of the WISC-R and the Halstead-Reitan Neuropsychological Test Battery with Learning-Disordered Children

The present investigation examined the neuropsychological constructs that underlie the Wechsler Intelligence Scale for Children-Revised (WISC-R). Data from administrations of the Halstead-Reitan Neuropsychological Test Battery (HRNB) and WISC-R were gathered for 1,079 learning-disabled children. A multiple regression analysis was employed to examine the contribution of each HRNB measure in the prediction of individual WISC-R subtests. Overall, verbal auditory discrimination presented as the most salient underlying construct of the WISC-R Verbal subtests, followed by concept formation and nonverbal auditory discrimination. Neuropsychological measures of the HRNB that involved perceptual organization were found to play a key role in defining the underlying constructs of the WISC-R Performance subtests. Similar to the above procedure, a second analysis was performed to assess the neuropsychological underpinnings of Kaufmans three factors (Verbal Comprehension, Perceptual Organization, and Freedom from Distractibility). Of the three factors, the HRNB measures explained similar amounts in the Freedom from Distractability (21%) and the Perceptual Organization (20.9%) factors in contrast to the Verbal Comprehension (7.3 %0) factor. Overall, these results indicate an interrelationship among several basic neuropsychological processes and higher-level cognitive functioning as represented on the WISC-R.

Underlying Factor Structure of Perinatal Events

The underlying factor structure of perinatal events was examined for 847 children (272 normals, 117 developmentally disabled, 37 speech disordered, 221 learning disordered, 91 emotionally disturbed, and 109 Head Start children). Pertinent perinatal information from the Maternal Perinatal Scale was subjected to a principle-components factor analysis. Ten factors accounting for some 58% of the total variance were isolated. In general, these factors appeared to be consistent with clinical evidence. The results were discussed in terms of their implications for the utility of perinatal information.