Patrick C. Fowler

Family Environment and Early Behavioral Development: A Structural Analysis of Dependencies

Structural analyses of the dependencies between early displays of behavior problems, e.g. aggression, developmental delay, and later family environmental structure are presented for a sample of 19 girls and 16 boys living in the northeastern U.S. Multiple regression analyses show a moderate order of predictability (R — .56, p < .01) for the regression of an “interpersonal relationships” index on five behavioral indices but a much lower order of predictability (R — .36, p < .05) for the regression of “organization-control” on these same indices. Although these cross-age (18-mo. interval) correlations are higher than would be expected on the basis of recent theoretical commentary in developmental psychology (Sameroff, 1975), the continuing need for consistent application of multivariate designs within the context of generative models (Barth, 1966) is conspicuous.

WAIS factor patterns of epileptic and normal adults

abstract The pattern and level of WAIS performance for 118 epileptic adults (65 men and 53 women) were compared to those of the standardization sample. As expected, epileptic subjects performed more poorly on all 11 subtests (from .61 to 1.17 SD below the norm group). Contrary to expectation, epileptic subjects were neither more variable nor were the inter-correlations of the subtests lower than those of the norm group. Overall, strong similarities in the patterns of performance on the tests were found for the two groups. As in previous research, factor analysis revealed the presence of a verbal comprehension factor, a perceptual organization dimension, and, in the instance of the three-factor solutions, an additional freedom-from-distractibility dimension for both groups.

Epilepsy, neuropsychological deficits, and EEG lateralization

One hundred eight epileptic patients (59 men, 49 women; 55% partial seizures, 45% generalized) were examined on 45 indices comprising a modified Halstead Neuropsychological Test Battery. Factor analyses identified five dimensions: Verbal Comprehension, Perceptual Organization, Selective Attention, Motor Skills, Abstract Reasoning. These factors are similar to those previously reported for neurocognitive abilities in several different populations. Relative deficits on Verbal Comprehension and Abstract Reasoning were related, as predicted, to left hemispheric dysfunction as indexed by EEG localization. Perceptual Organization demonstrated a further, predictable relationship to right hemispheric function. Deficits on Selective Attention were not clearly lateralized, being correlated with a wide variety of electroencephalographic abnormalities. The implications of these findings for the use of neurocognitive profiles in treatment planning for this population are discussed.

A multifactor model of the Halstead‐Reitan neuropsychological test battery and its relationship to cognitive status and psychiatric diagnosis

An oblique, five-factor model of a modified Halstead-Reitan Neuropsychological Test Battery is presented. One hundred fifty-one neuropsychiatric inpatients (94 men, 57 women) were examined on 44 neuropsychological indices. Five correlated dimensions (r = .25), viz., Verbal Comprehension, Perceptual Organization, Sensory-attention, Primary Motor, and Tactile-spatial abilities, were identified by maximum likelihood factor analyses of this correlation matrix. These findings are quite similar to those reported earlier by Fowler, Richards, Berent, and Boll (1985, 1987) and Royce, Yeudall, and Bock (1976). The factors may be broadly categorized using the distinction made by Lezak (1983) for verbal, nonverbal, and mental activity variables. MANOVAs revealed systematic relationships between simple-weighted factor scores and: (1) the overall level of cognitive functioning (p less than .01), as well as (2) psychiatric diagnosis (p less than .01). Implications of these findings for understanding the impact of neuropsychiatric disorders on the structure of abilities for such patients are developed.

Wechsler Verbal-Performance IQ discrepancies among psychiatric inpatients: Implications for subtle neuropsychological dysfunctioning

One hundred seventy-nine psychiatric inpatients were administered the WAIS-R and several neuropsychological and academic achievement tests. All subjects were assigned to three groups based on their WAIS-Rs VIQ-PIQ discrepancy scores: (i) Low Verbal (Verbal IQ < Performance IQ. by at least 13 points); (ii) Low Performance (Performance IQ < Verbal IQ by at least 13 points); and (iii) Equal (Verbal IQ-Performance IQ within 13 points). The Low Verbal group made significantly more errors on the Speech Sounds Perception Test, demonstrated lower spelling scores, evinced more aphasic signs, and had had more special education placements than did the Equal or Low Performance groups. The Low Performance subjects demonstrated significantly more signs of constructional dyspraxia and performed more poorly on the Grooved Pegboard test. The neuropsychiatric patients who had Verbal-Performance IQ discrepancies of at least one standard deviation may be at risk for specific, subtle neuropsychological deficits.

Comparison of wisc-r factor patterns for younger and older epileptic children

Abstract The pattern and level of WISC-R performances were examined for 113 younger (ages 6–12) and 124 older (ages 12–16) epileptic children. Although these youngsters performed more poorly than the norm group on all 10 subtests, as do adult epileptics on the WAIS (Fowler, Richards, & Boll, 1980), only the younger subjects showed a definite tendency to be more variable in their performance. Factor analyses demonstrated the presence of highly similar Verbal Comprehension and Perceptual Organization dimensions for both groups but, in the case of the 3-factor solutions, an additional freedom-from-distractibility dimension was found for only the older subjects. These results suggest that Kaufmans (1975, 1979) 3-factor model of the Wechsler scales is more strongly approximated as the age of the epileptic respondents increases.

Confirmatory maximum likelihood factor analyses of the personality research Form-E

Two confirmatory maximum likelihood factor analytic models of the Personality Research Form-E are presented and discussed for the mens and womens standardization data (Jackson, 1974) (N = 215). The two models investigated were: (1) a six-factor model based on Jacksons conceptual framework for the Personality Research Form-E; and (2) the five-factor empirical model advanced by Fowler (1985). Overall, the patterns of correlations within each data matrix are highly similar, but the factor patterns, factor intercorrelations, as well as the error variances, do differ. The five-factor model was found to be more adequate generally, but produced no absolute fit to the data matrices, while the six-factor model invariably produced inaccurate estimates of the parameters. Comparisons of the completely estimated, Varimax-rotated factor loading matrices to that reported by Fowler found, on the whole, stronger similarity between matching factors for the women than for the men. The implications of this finding for the modelling of the PRF-E and its application in clinical contexts are considered at length.

WAIS‐R factors and performance on the Luria‐Nebraska's intelligence, Memory, and Motor Scales: A canonical model of relationships

The pattern and level of performance on the WAIS-R and the Luria-Nebraskas Intelligence, Memory, and Motor Scales were examined for 93 neurologically impaired adults. Maximum likelihood factor analyses of the WAIS-R indicated the presence of strongly correlated (.72) Verbal Comprehension and Perceptual Organization dimensions. Comparisons of these factors to those of the standardization group revealed an acceptable level of similarity (.94) for Verbal Comprehension, but not for Perceptual Organization (.53). Canonical correlations between WAIS-R factor scores and the three Luria-Nebraska scaled scores accounted for 82% of the total variance. Each set of procedures evidently is indexing the same theoretical constructs. Implications of these findings for our understanding of the measurement models that underlie clinical neuropsychology are discussed.

Trait analyses of the Luria-Nebraska Intellectual Processes, Motor Functions, and Memory Scales.

Trait analyses of the Luria-Nebraskas Intellectual Processes, Motor Functions, and Memory Scales were performed using multitrait-multimethod procedures and confirmatory factor analysis. Three measures each of intellectual, motor, and memory functions were administered to 161 neuropsychiatric patients. Intellectual scales (viz., Luria-Nebraska and WAIS-R) were found to have convincing discriminant properties, but motor and memory measures demonstrated visibly less such robustness. Confirmatory factor analyses supported a three-factor model of the 9 x 9 matrix, in which each of the three Luria-Nebraska scales serves as a marker for the factors. Issues related to the neuropsychological constructs, test construction, and construct validity of measurement procedures employed in clinical neuropsychology are discussed.

WAIS factor pattern for neuropsychiatric inpatients

The current study examines the factor pattern of the Wechsler Adult Intelligence Scale for a sample of 151 neuropsychiatric inpatients (97 men, 54 women). As expected, these patients performed less well on all 11 of the subtests and ranged from .60 to 1.54 SD below normative standards. These patients were neither more variable nor were the intercorrelations among the subtests lower than those of the normative group. As in previous research, maximum likelihood factor analyses revealed the presence of a Verbal Comprehension dimension and a Perceptual Organization dimension, factors that were moderately correlated (.60). The stability of a two-factor solution for the WAIS in this population and its implications for the inclusion of the WAIS as a component of a neuropsychological assessment paradigm are discussed.