Nonverbal learning disabilities: A critical review

This article presents a critical review of the term and concept of nonverbal learning disability (NLD). After a brief historical introduction, the article focuses on the apparent rarity of NLD; the hypothesis of the frequent co-occurrence of emotional disorder, depression, and suicide in NLD; the white matter hypothesis as an explanation of the origin of NLD; and the question of NLD as part of a variety of other disorders. It is argued that NLD presents a broad hypothesis, but that there is little evidence to support its use in clinical practice.     

Visual Perception and Memory Impairments in Children at Risk of Nonverbal Learning Disabilities

Visuospatial working memory (VSWM) and visual perception were examined in two groups aged 11–13, one with children displaying symptoms of nonverbal learning disability (NLD) (n = 18) and the other a control group without learning disabilities (n = 18). The two groups were matched for general verbal abilities, age, gender, and socioeconomic level. The children were presented with VSWM tests involving visual and spatial-simultaneous processes, and also with a classical visual illusion, a classical ambiguous figure, as well as visual perception tests specifically devised for the present study. Results revealed that performance of children at risk of NLD was worse than controls in some VSWM and in visual perception tests without memory involvement; these latter required comparisons of visual stimuli and locations in space with distractors. Moreover, the two groups differed in perceiving the classical ambiguous figure. Findings are discussed in the light of both theoretical and clinical implications.     

Validity of a short form of the WISC-III in children with traumatic head injury

The concurrent, construct, and criterion validities of Donders' (in press) short form of the Wechsler Intelligence Scale for Children - Third Edition (WISC-III) were evaluated in a sample of 171 children with traumatic head injury (THI). Correlations between the short-form deviation quotients and their full-length counterparts were statistically significant. Confirmatory factor analysis revealed that a four-factor model (composed of Verbal Comprehension, Perceptual Organization, Freedom from Distractibility, and Processing Speed) fit the data relatively well. The short-form deviation quotients also had statistically significant correlations with length of coma. It is concluded that this short form is an accurate and valid alternative to the full-length WISC-III in children with THI.     

Memory for symmetry and perceptual binding in patients with schizophrenia

The present study investigated the use of perceptual binding processes in schizophrenic (SC) patients and matched healthy controls, by examining their performance on the recall of symmetrical (vertical, horizontal and diagonal) and asymmetrical patterns varying in length between 2 and 9 items. The results showed that, although SC patients were less accurate than controls in all conditions, both groups recalled symmetrical patterns better than asymmetrical ones. The impairment of SC patients was magnified with supra-span symmetrical arrays, and they were more likely to reproduce symmetrical patterns as asymmetrical, particularly at medium and high length levels. Hierarchical regression analyses further indicated that the between-group differences in the recall of supra-span vertical and horizontal arrays, which require a greater involvement of visual pattern processes, remained significant after removing the variance associated with performance on asymmetrical patterns, which primarily reflects intrafigural spatial processes. It is proposed that schizophrenia may be associated with a specific deficit in the formation and retrieval of the global visual images of studied patterns and in the use of the on-line information about the type of symmetry being tested to guide retrieval processes.     

Development and Initial Validation of a General Psychological Well-being Scale (GPWS) in an African Context

This study aimed to develop and validate the General Psychological Well-being Scale (GPWS) in an African sample, based on the empirical overlap between hedonic and eudaimonic facets of well-being as found in previous research. The quantitative cross-sectional study was conducted in three phases: secondary data analysis (n = 2005), pilot study (n = 296) and main study (n = 459). The pilot and main study included the GPWS as well as other psychological well-being measures for criterion-related validity. The pilot study yielded satisfactory psychometric properties. The main study yielded a high, reliable Cronbach alpha of.89 and evidence of construct validity. The GPWS appears to be a unidimensional scale suitable for research use with Setswana-speaking people.     

Emotional Intelligence and the Identity Negotiation of a Racial Minority Group in a Majority School Context

This article describes the possible impact of emotional intelligence on identity negotiation of a racial minority group in a majority school context. The study investigated the adjustment and functioning of racial minority groups in majority school contexts, as well as the identity negotiation associated with it, and determined whether there is a correlation between the former and the Emotional Intelligence (EI) of the participants. Participants were 16 black and 21 white learners attending two schools where they were in the minority (mean age = 16.23 years; SD = 1.49 years). The learners attended Grades 9–12. Data were first organised, after which themes and patterns were identified, and the data appraised and categorised (Creswell, 2007), after which a comparison was drawn between the identified categories of existing knowledge. Findings suggest that racial integration in both high schools actually occurred in name only; most participants chose to mingle within their own racial groups and the black participants in particular were exposed to racism, discrimination and prejudice on a regular basis. Despite the necessary steps taken and implemented by government in order to oppose racism in the country and promote racial integration in schools, it seems that the consequences of apartheid remain for the foreseeable future.     

Measuring resilience among homeless youth: psychometric assessment of the Connor-Davidson Resilience Scale in Ghana

This study validated the psychometric structure of the Connor-Davidson Resilience Scale (CD-RISC; Connor & Davidson, 2003 Connor, K. M., & Davidson, J. R. T. (2003). Development of a New Resilience Scale: The Connor–Davidson Resilience Scale (CD-RISC). Depression and Anxiety, 18, 76–82. doi: 10.1002/da.10113[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) in a sample of 227 homeless youth in Ghana. Principal Component Analysis (PCA) with Varimax rotation was used to extract factor structures. About 62% of the total variance was accounted for by a three-factor structure: personal competence and tenacity, optimism and achievement motivation. Evidence of the external validity of scales was supported by the positive correlation between resilience and perceived social support scores. The CD-RISC appears to yield scores reliable for assessing resilience among homeless youth in a developing world context.     

Psychometric Properties of the Short Self-Regulation Questionnaire (SSRQ) in a South African Context

Self-regulation (SR), an important construct within the psychological well-being context, involves the ability to monitor behaviour, to contrast it with reference values and to introduce adjustments where necessary. A lack of validated measures of SR in the South African context has contributed to the current caveat in our knowledge of the potential importance of this construct. This investigation aimed to establish the utility of the Short Self-Regulation Questionnaire (SSRQ; Carey, Neal & Collins, 2004) in a South African context. This short version of the original Self-Regulation Questionnaire (SRQ; Brown, Miller & Lawendowski, 1999) was completed by a group of 385 undergraduate psychology students. Factor analysis produced 7 factors, all of which showed significant positive correlations with other measures of psychological well-being. This first step toward establishing the importance of SR in non-Western cultures reflected positively on the potential use of the SSRQ in large epidemiological studies.     

Probabilities on Sentences in an Expressive Logic

Automated reasoning about uncertain knowledge has many applications. One difficulty when developing such systems is the lack of a completely satisfactory integration of logic and probability. We address this problem directly. Expressive languages like higher-order logic are ideally suited for representing and reasoning about structured knowledge. Uncertain knowledge can be modeled by using graded probabilities rather than binary truth values. The main technical problem studied in this paper is the following: Given a set of sentences, each having some probability of being true, what probability should be ascribed to other (query) sentences? A natural wish-list, among others, is that the probability distribution (i) is consistent with the knowledge base, (ii) allows for a consistent inference procedure and in particular (iii) reduces to deductive logic in the limit of probabilities being 0 and 1, (iv) allows (Bayesian) inductive reasoning and (v) learning in the limit and in particular (vi) allows confirmation of universally quantified hypotheses/sentences. We translate this wish-list into technical requirements for a prior probability and show that probabilities satisfying all our criteria exist. We also give explicit constructions and several general characterizations of probabilities that satisfy some or all of the criteria and various (counter)examples. We also derive necessary and sufficient conditions for extending beliefs about finitely many sentences to suitable probabilities over all sentences, and in particular least dogmatic or least biased ones. We conclude with a brief outlook on how the developed theory might be used and approximated in autonomous reasoning agents. Our theory is a step towards a globally consistent and empirically satisfactory unification of probability and logic.