Using the MMPI–2–RF to Discriminate Psychometrically Identified Schizotypic College Students From a Matched Comparison Sample

This study investigates the extent to which the Minnesota Multiphasic Personality Inventory–2 Restructured Form (MMPI–2–RF) profiles of 52 individuals making up a psychometrically identified schizotypes (SZT) sample could be successfully discriminated from the protocols of 52 individuals in a matched comparison (MC) sample. Replication analyses were performed with an additional 53 pairs of SZT and MC participants. Results showed significant differences in mean T-score values between these 2 groups across a variety of MMPI–2–RF scales. Results from discriminant function analyses indicate that schizotypy can be predicted effectively using 4 MMPI–2–RF scales and that this method of classification held up on replication. Additional results demonstrated that these MMPI–2–RF scales nominally outperformed MMPI–2 scales suggested by previous research as being indicative of schizophrenia liability. Directions for future research with the MMPI–2–RF are suggested.     

Illness perceptions and self efficacy beliefs in adolescents and young adults with insulin dependent diabetes mellitus

Abstract

The study examined the role of illness perceptions and self-efficacy in diabetic regimen adherence and metabolic control among young patients with Insulin Dependent Diabetes Mellitus (IDDM). Sixty-four outpatients with Insulin Dependent Diabetes completed measures of illness perceptions, generalised and diabetes specific self-efficacy and a self-report measure of adherence. Metabolic control (HbAlc) was also assessed. Control, identity and consequences components of illness perceptions were significantly correlated with self-efficacy expectancies. Control beliefs were consistently associated with self-reported adherence across all treatment aspects and accounted for 39% of the predicted variance in total adherence. The associations of the other psychological predictors examined, varied depending on the regimen area. Multiple regression analysis showed that 30.8% of the variance in HbAlc assays was explained by patients' diabetes specific self-efficacy, consequences and identity. Our findings suggest that patients' beliefs are useful predictors of physiological and behavioural outcomes in diabetes self-management and should thus be the focus of routine clinical assessments and future interventions.     

Different mechanisms of fear extinction dependent on length of time since fear acquisition

Fear extinction is defined as a decline in conditioned fear responses (CRs) following nonreinforced exposure to a feared conditioned stimulus (CS). Behavioral evidence indicates that extinction is a form of inhibitory learning: Extinguished fear responses reappear with the passage of time (spontaneous recovery), a shift of context (renewal), and unsignaled presentations of the unconditioned stimulus (reinstatement). However, there also is evidence to suggest that extinction is an "unlearning" process corresponding to depotentiation of potentiated synapses within the amygdala. Because depotentiation is induced more readily at short intervals following LTP induction and is not inducible at all at a sufficient delay, it may be that extinction initiated shortly following fear acquisition preferentially engages depotentiation/"unlearning," whereas extinction initiated at longer delays recruits a different mechanism. We investigated this possibility through a series of behavioral experiments examining the recoverability of conditioned fear following extinction. Consistent with an inhibitory learning mechanism of extinction, rats extinguished 24-72 h following acquisition exhibited moderate to strong reinstatement, renewal, and spontaneous recovery. In contrast, and consistent with an erasure mechanism, rats extinguished 10 min to 1 h after acquisition exhibited little or no reinstatement, renewal, or spontaneous recovery. These data support a model in which different neural mechanisms are recruited depending on the temporal delay of fear extinction.     

Relationship between eight physiological variables and severity of stuttering

The results of this study illustrated the primacy of individual differences in the relationship between physiological responses before speech and stuttering severity.     

Adolescents' Misperceptions of the Dangerousness of Acetaminophen in Overdose

Clinical observations suggest that adolescents commonly and naively use acetaminophen in suicide attempts even when they do not wish to die. It is estimated that 18 500-mg acetaminophen tablets can lead to hepatotoxicity, while death is usually associated with ingestion of 50 or more tablets. A sample comprising 569 adolescent students completed an author-designed survey assessing teenagers' knowledge of acetaminophen's therapeutic and harmful effects. The findings support our original data that adolescents have ready access to acetaminophen and use it in suicide attempts, but underestimate its potential for toxicity. Forty-two percent of this sample underestimated the dose to cause harm, believing it would require 20 or more tablets, and 50% underestimated the dose to cause death, stating 100 or more pills would be necessary. Adolescents appear to seriously underestimate the dangerousness of acetaminophen in overdose, and lack knowledge regarding side effects of overdose.     

Influences on Member Assimilation in Workgroups in High‐Reliability Organizations: A Multilevel Analysis

This multilevel investigation examined the effect of group interaction and its influence on individual‐level membership variables and group assimilation. The study is based on a model of group socialization developed by Moreland and Levine (1982) and was modified in this study to investigate the development and maintenance of highly interdependent workgroups in a high‐reliability organization: a municipal fire department. Using hierarchical linear modeling, we examined individual‐ and crew‐level influence on four assimilation outcomes: involvement, trustworthiness, commitment, and acceptance. At the individual level, acculturation predicted all the four assimilation outcomes. Involvement also was a predictor of the latter sequences of assimilation: commitment and acceptance. The study also found that one crew‐level variable—crew performance—affected and modified the influence of tenure, proactivity, involvement, acculturation, and trust on members’ commitment. Implications are offered for the influence of group interaction on member assimilation and support for continuing group‐level research on assimilation. This study also underscores the utility of multilevel analysis in examining communication at the interpersonal and group levels.