Stochastic dynamics of stimulus encoding in schizophrenia: Theory, testing, and application

Cognitive processing among schizophrenia participants, entailing encoding of presenting stimulation into a format facilitating collateral processes (e.g., memory search), is examined in light of stochastic mathematical models of performance. Results implicate additional encoding operations (encoding subprocesses) as the source of schizophrenia encoding-process elongation. Convergent evidence for this inference, including that from auxiliary neuro-connectionist simulations, are brought forth. Developments from initial, fixed-parameter accounts include random-parameter mixtures, and their Bayesian extensions, formally mediating group-level results to assessment of individual performance. Outgrowths bear on model-selection methodology, according to coherence of group-level and individual-level model functioning (in part addressing the issue of “small-trial-sample model testing”); longitudinal monitoring of encoding-specific treatment response; evaluation of treatment-regimen efficacy with respect to encoding efficiency; and specification of times of measurement interest, in fMRI. The symptom significance of encoding elongation, strongly hinted at by model developments, along with a model-endowed window on exacerbating effects of stress, are drawn out.     

A longitudinal investigation of the reliability of memories for trauma and other emotional experiences

This study examined the relative consistency and characteristics of memories for trauma and other non‐traumatic emotional experiences over time. A community sample of 52 participants who reported a recent traumatic event were asked to recall both the traumatic and a positive emotional experience in two interviews separated by approximately three months (M = 105.39 days). The recollections were elicited with either a free narrative, cognitive interview, guided imagery, or written narrative approach. Results indicated that traumatic experiences were recalled more reliably over time than other emotional experiences. Traumatic memory imagery tended to persist in memory (with no apparent impairment), whereas features of positive memories were subject to considerable distortion, regardless of interview style. The findings contribute to the understanding of the impact of trauma on memory with the passage of time. Copyright © 2004 John Wiley & Sons, Ltd.     

The Social Roles Questionnaire: A New Approach to Measuring Attitudes Toward Gender

Innovative research is constrained by instruments that assume gender to be captured by dichotomous categories. This article presents the results of two studies that document the psychometric properties of the Social Roles Questionnaire (SRQ), a new measure of gender role attitudes. A social constructivist perspective guided the development of the instrument that was designed not only to capture the diversity in people’s thinking about social roles for men and women, but also to identify attitudes that transcend binary categories. The article details the process of assessing reliability and validity based on data from 414 undergraduates. Findings revealed the SRQ is reliable and valid and that women were more likely than men to endorse egalitarian and gender transcendent beliefs. Additional possible uses of the SRQ are discussed.     

Performance of children with epilepsy and normal age-matched controls on the WISC-III.

Research findings regarding the effects of childhood epilepsy on general intelligence have produced variable results. The aim of this study was to investigate the effects of epilepsy, age of seizure onset, and Antiepileptic Drugs (AED) on intellectual ability as assessed by the Wechsler Intelligence Scale for Children, 3rd Edition (WISC-III; Wechsler, 1991). This study included children with epilepsy assessed with the WISC-III who achieved either a Full Scale, Verbal Scale, or Performance Scale IQ score >or= 70. A clinical sample of children diagnosed with epilepsy (n = 32) were age- and gender-matched with subjects from the normative standardization sample for the WISC-III, yielding a total sample of 64 subjects. Comparison using a MANOVA revealed significant differences across WISC-III Index standard scores (p = 0.0005) and subtest scaled scores (p = 0.0013), with control participants performing better than epileptic participants. Secondary analyses were also conducted considering monotherapy (n = 14) versus polytherapy (n = 11), and age of seizure onset (<6 years, n = 12; 6 > years, n = 15). MANOVA comparisons revealed no significant differences between groups across WISC-III Index standard scores.     

A comparison of children with epilepsy to an age- and IQ-matched control group on the Children's Memory Scale.

Past research has found that children with epilepsy exhibit decreased memory skills. In addition, some studies have found that children with epilepsy obtain significantly lower IQ scores than controls. In an effort to examine whether children with epilepsy have specific memory weaknesses versus global cognitive difficulties, the present study compared the performance of 62 children (age range = 6-16 years). Thirty-one children with epilepsy were compared to 31 age- and IQ-matched controls on the Children's Memory Scale (CMS) to determine whether differences in memory skills persist when IQ is matched. An independent t-test comparing index and scaled scores was performed. The results indicated that with the exception of the Word Pairs subtest (p < .01), children with epilepsy did not differ significantly on the CMS subtests when IQ was matched. This suggests that list-learning paradigms may be particularly sensitive to memory impairments in children with epilepsy and/or that children with epilepsy have more global cognitive impairments.     

Automatic stereotypes vs. automatic prejudice: Sorting out the possibilities in the weapon paradigm

Payne (2001) has documented that African-American faces automatically facilitate the categorization of handguns, relative to White faces. We suggest that these provocative results could derive from either the automatic activation of prejudice (negative evaluations) or the automatic activation of stereotypes (both positively and negatively valenced associations). In an extension of Payne’s procedure, we show that African-American faces facilitate the categorization of both handguns and sports-related objects, but not the categorization of insects or fruits. Additionally, both handguns and sports objects are more likely to be miscategorized following a White face prime than an African-American one. These results suggest that when perceivers are attempting to identify objects, automatic stereotypic associations, both positively and negatively valenced ones, are more influential than general negative sentiments towards African-Americans.     

Selection of variables in exploratory factor analysis: An empirical comparison of a stepwise and traditional approach

The purpose of this study was to investigate and compare the performance of a stepwise variable selection algorithm to traditional exploratory factor analysis. The Monte Carlo study included six factors in the design; the number of common factors; the number of variables explained by the common factors; the magnitude of factor loadings; the number of variables not explained by the common factors; the type of anomaly evidenced by the poorly explained variables; and sample size. The performance of the methods was evaluated in terms of selection and pattern accuracy, and bias and root mean squared error of the structure coefficients. Results indicate that the stepwise algorithm was generally ineffective at excluding anomalous variables from the factor model. The poor selection accuracy of the stepwise approach suggests that it should be avoided.     

Performance in auditory and visual emotional stroop tasks: a comparison of older and younger adults

Research has shown age-related declines in the cognitive ability to inhibit irrelevant information. Thirty-six younger adults (mean age = 22 years) and 36 older adults (mean age = 74 years) performed 2 versions of an emotional Stroop task. In one, they made lexical decisions to emotion words spoken in 1 of several tones of voice. Latencies were longer for test words spoken in an incongruent tone of voice, but only for older adults. In another, words were displayed on a computer screen in a colored font, and participants quickly named the font color. Latencies were longer for test words high on arousal, but only for older adults. Results are discussed in terms of inhibitory cognitive processes, attention, and theories of emotional development.