Arturo Orsini

Effects of Age, Education and Sex on Two Tests of Immediate Memory: A Study of Normal Subjects from 20 to 99 Years of Age:

Spatial span (Corsis block-tapping test) and verbal span (Wechsler Digits Forward) were measured in 1354 normal subjects, aged from 20 to 99 yr., who were subdivided into seven age groups, into three groups according to education, and according to sex. Analysis of variance showed that the three main factors were significant for the spatial span test, while only age and education were significant for the verbal span test. The two spans examined held well up to the 60s, and only after this age did significant differences appear in the other age groups. On both tests there were significant differences between the groups divided according to education.

SEX AND CULTURAL DIFFERENCES IN CHILDREN'S SPATIAL AND VERBAL MEMORY SPAN

Spatial span (Corsis block-tapping) and verbal span (Wechsler Digits Forward) were measured in 1113 children aged 4 to 10 yr. from urban and rural districts of the Regione Campania. Significant differences pointing to a better performance of the “town” group were found on both tests. Sex differences were found only on the spatial span rest; boys performed better than girls.

Differences in the intellectual profile of children with intellectual vs. learning disability.

The WISC-IV was used to compare the intellectual profile of two groups of children, one with specific learning disorders (SLDs), the other with intellectual disabilities (ID), with a view to identifying which of the four main factor indexes and two additional indexes can distinguish between the groups. We collected information on WISC-IV scores for 267 children (Mage=10.61 [SD=2.51], range 6-16 years, females=99) with a diagnosis of either SLD or ID. Children with SLD performed better than those with ID in all measures. Only the SLD children, not the ID children, revealed significant differences in the four main factor indexes, and their scores for the additional General Ability Index (GAI) were higher than for the Cognitive Proficiency Index (CPI). Children with a diagnosis of SLD whose Full-Scale Intelligence Quotient (FSIQ) was <85 showed a similar pattern. Our findings confirm the hypothesis that children with SLD generally obtain high GAI scores, but have specific deficiencies relating to working memory and processing speed, whereas children with ID have a general intellectual impairment. These findings have important diagnostic and clinical implications and should be considered when making diagnostic decisions in borderline cognitive cases.

Corsi's Block-Tapping Test: Standardization and Concurrent Validity with WISC—R for Children Aged 11 to 16

Corsis block-tapping test and WISC—R were given to 1122 children from 11 to 16 years of age. Corsis raw scores were transformed into standard scores like those for the WISC—R subtests. Reliabilities, standard score equivalents of raw scores, correlations with scores on WISC—R subtests, scales and factor scores are presented. A Principal Factor analysis of intercorrelations for Corsis test and WISC—R subtests shows a three-factor solution with Corsis test loading on the Third Factor. Results agree with Wielkiewiczs (1990) hypothesis about the construct underlying WISC—R Third Factor as “executive” and short-term memory processes.

Factor structure of the Italian version of the WAIS-R compared with the American standardization.

Factor analysis for responses to the WAIS–R by 1,630 adults of the Italian standardization sample produced two factor solutions in different age groups, and showed high factorial similarity when compared with the same American solution. An estimate of g factor and variance components showed some difference with American data: a lower proportion of g and common variance, and a greater specificity characterized the Italian version with an almost identical error variance. For both the estimate of g and variance components some change across age groups was observed with g and common variance increasing and specific variance decreasing from youngest to oldest groups.

“Experimental Amnesia” Induced by Emotional Items

Tulving described an effect of retrograde amnesia in a free-recall task of word lists, produced by inserting items having priority in recall. Other authors confirmed the amnesic effect without giving instructions for priority both in recall and in recognition tasks. The effect was explained by Tulving as a premature termination of encoding processes. The similarity between these experiments and the researches aimed at reproducing amnesia by emotional trauma led us to hypothesize that the two phenomena might be due to the same functional mechanisms. We have organized a free-recall task of word lists into which emotional items were inserted. Our aim was to verify whether with these experimental conditions Tulvings results would be reproduced. The obtained data show amnesic effects in free recall; nevertheless, they do not seem to confirm closely the experimental hypothesis. Lastly, changes in primacy and recency effects produced by emotional items are analyzed.

Verbal and Spatial Memory Span in Patients with Extrapyramidal Diseases

Spatial span (Corsis block-tapping test) and verbal span (Wechslers Digits Forward test) were measured in 651 normal subjects and in three groups of extrapyramidal patients (Progressive supranuclear palsy, Parkinson, and Huntingtons Chorea). Analysis showed Huntingtons Chorea patients scored lower on both tests than did controls and other groups.

Corsi's Block-Tapping Test: Some Characteristics of the Spatial Path Which Influence Memory

By using a sequence of digits it is possible to indicate the path of Corsis block-tapping test by drawing a line to join the central points of the cubes which make up the sequence. By doing this one can analyze the sequence of digits according to quantitative parameters. There were three characteristics of the spatial path taken into consideration in this research: the number of cubes which constitute a series of digits, the number of times the path intersected itself, and the length of the path measured in millimeters. The experiment, carried out with 70 university students, showed that all three factors were significant on analysis of variance, and also that there were differences between the sexes, the men performing better. No interactions were significant. Despite this, additional significant differences were found among the series with the same number of cubes, intersections, and length, meaning that other variables influence the difficulty of the spatial path.

Structure of the Wechsler Adult Intelligence Scale – Revised in the Italian Normal Standardisation Sample

Six multifactor correlated traits models and a single-factor model of the WAIS-Rs factor pattern were examined by confirmatory maximum likelihood factor analyses of a data matrix from the WAIS-Rs Italian normative sample raw scores (N=2284). The main aim was to identify what model(s) best fit(s) the data for the different age groups considered. Analyses were designed to determine which of seven hypothesised factor solutions best explained the intellectual ability of four age bands (16 to 74 years of age) and of all samples. Results showed the same three-correlated-factors model (Verbal, Performance, and Freedom From Distractibility) for the younger (16 to 24 years of age) and for more aged (65 to 74 years of age), and two different three-factor models for the adult (band from 25 to 64 years of age) that had in common the presence of Digit Symbol loading on Freedom From Distractibility, that in the younger and aged band loaded on Perceptual Organisation. The individuals may use different strategies when performing a given task on the WAIS-R. Such differences in latent variability may represent real differences in neuropsychological functioning, and as such can account for some of the variability in results noted in the literature. Differences in latent variability across distinct demographic and clinical groups could provide important insight into brain–behaviour relationships.

The Unitary Ability of IQ and Indexes in WAIS-IV

Lichtenberger and Kaufman (2009, p. 167) defined unitary ability as “an ability […] that is represented by a cohesive set of scaled scores, each reflecting slightly different or unique aspects of the ability.” Flanagan and Kaufman (2009) and Lichtenberger and Kaufman (2012), to define unitarity of IQ, use a difference of 23 IQ points between the highest score (Max) and the lowest score (Min) obtained by a subject in the four Indexes of WAIS-IV. A similar method has been used to assess the unitary ability for the four Indexes, with the threshold of 5. Such difference score (of 23 for IQ and 5 for Indexes) are considered high and infrequent and, the authors therefore conclude that the corresponding Full-Scale IQ score or Index score is uninterpretable. In this paper we argue that these thresholds are inappropriate because they are based on the wrong standard deviation. The main aim of this study was to establish variability thresholds for IQ and the WAIS-IV Indexes for the American standardization sample and to compare these thresholds with those for the Italian standardization sample. We also consider an alternative approach to determining whether an IQ score represents a unitary ability based on the maximum difference score for the 10 core subtests that contribute to Full-Scale IQ.