Using PsyScope for demonstrations and student-designed experiments in cognitive psychology courses

We describe a plan for integrating an experimental control language, PsyScope, into under-graduate laboratory exercises of perceptual and cognitive experiments on Macintosh computers. PsyScope is a powerful and versatile system with which students can modify standard research paradigms and execute experiments of their own design, thus facilitating student-initiated independent research. Data are summarized with a general-purpose program, PsySquash, for import into Statview or SuperAnova for further analysis. This system provides an effective means of implementing student projects.     

Investigating Correlates of Suicide Among Male Youth: Questioning the Close Affinity Between Suicide Attempts and Deaths

This study was based on a sample of male high school students who completed National Longitudinal Adolescent Health Surveys in 1994, 1995, and 2001. We studied these students prospectively, comparing those who later died by suicide (n = 21) with those who were still living (n = 10,101). We employed chi‐square and analysis of variance tests for statistical significance between suicide decedents and living respondents. Results showed suicide decedents were more likely to have experienced the suicide loss of another family member, to have been expelled from school, to have engaged in more delinquent actions including fighting, and to have greater involvement with the criminal justice system. Although one might have expected suicide casualties to have exhibited a greater amount of suicidal thoughts, attempts, and higher incidences of suicidality among their friends, our analyses did not find that these factors were associated with actual suicides. Should these findings be replicated, this would point to a need to refine youth suicide risk assessments. Collecting life histories, as well as identifying patterns of delinquency and fighting, may serve as more potentially fruitful means for assessing genuine suicide risk than some traditional risk assessment methods.z     

Positive and Negative Expectations of Hopelessness as Longitudinal Predictors of Depression,Suicidal Ideation,and Suicidal Behavior in High‐Risk Adolescents

The relationship between hopelessness and depression in predicting suicide‐related outcomes varies based on the anticipation of positive versus negative events. In this prospective study of adolescents at elevated risk for suicide, we used two Beck Hopelessness Scale subscales to assess the impact of positive and negative expectations in predicting depression, suicidal ideation, and suicidal behavior over a 2‐ to 4‐year period. In multivariate regressions controlling for depression, suicidal ideation, and negative‐expectation hopelessness, positive‐expectation hopelessness was the only significant predictor of depressive symptoms and suicidal behavior. Clinical interventions may benefit from bolstering positive expectations and building optimism.     

On Johnson's (2000) Relative Weights Method for Assessing Variable Importance: A Reanalysis

This article provides a reanalysis of J. W. Johnson's (2000) “relative weights” method for assessing variable importance in multiple regression. The primary conclusion of the reanalysis is that the derivation of the method is theoretically flawed and has no more validity than the discredited method of Green, Carroll, and DeSarbo (1978) on which it is based. By means of 2 examples, supplemented by other results from the literature, it is also shown that the method can result in materially distorted inferences when it is compared with another widely used importance metric, namely, general dominance (Azen & Budescu, 2003; Budescu, 1993). Our primary recommendation is that J. W. Johnson's (2000) relative weights method should no longer be used as a variable importance metric for multiple linear regression. In the final section of the article, 2 additional recommendations are made based on our analysis, examples, and discussion.     

Coordinating cognitive information: task effects and individual differences in integrating information from several sources.

In many tasks people have to coordinate the information from several sources. An example would be driving a car while listening to directions. The driver has to establish a correspondence between a visual picture and verbal instructions. This paper addresses two questions concerning information coordination. Is there an ability to coordinate information received from several sources that is different from the ability to deal with information from each source, alone? Does coordination simply involve allocating resources to deal with the component tasks, or does the act of coordination itself constitute a separate task? Four experiments examined the coordination of a verbal component task with a visual-spatial and with an auditory component task. The results showed that the ability to coordinate perceptual and verbal information is separate from the ability to deal with either perceptual or verbal information, alone. A simple resource sharing model was not adequate in explaining how coordination occurred. We relate our results to a model in which perceptual reasoning occurs independently of verbal processing, but transforming perceptual information into a propositional form is affected by concurrent verbal processing.     

Improving computer skill training: behavior modeling, symbolic mental rehearsal, and the role of knowledge structures

Effective computer skill training is vital to organizational productivity. Two experiments (N = 288) demonstrated that the behavior modeling approach to computer skill training could be substantially improved by incorporating symbolic mental rehearsal (SMR). SMR is a specific form of mental rehearsal that establishes a cognitive link between visual images and symbolic memory codes. As theorized, the significant effects of SMR on declarative knowledge and task performance were shown to be fully mediated by changes in trainees' knowledge structures. The mediational role of knowledge structures is expected to generalize to other training interventions and cognitive skill domains. Our findings have the immediate implications that practitioners should use SMR for improving the effectiveness of computer skill training.     

A biopsychosocial model for treating infertility

With approximately one out of six married couples experiencing infertility, having a basic knowledge of infertility is important to marriage and family therapists. This paper presents important themes that infertile couples often struggle with and stresses the importance of having a biological, psychological, and social understanding of infertility. In addition, the paper suggests possible interventions that family therapists can use in helping infertile couples.     

Effects of Acute Stress or Centrally Injected Interleukin-1beta on Neuropeptide Expression in the Immune System

Acute stress stimulates the expression and release of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) from the hypothalamus, and the pro-opiomelanocortin products beta-endorphin and ACTH from the anterior pituitary. These neuropeptides are also expressed in immune tissues, and it has been proposed that they may modulate immune responses to stress through paracrine mechanisms. We subjected rats to restraint stress or central injection of interleukin (IL)-1beta to determine whether these acute stimuli can alter the expression of neuropeptides in the spleen and thymus. Restraint stress significantly increased the contents of all these neuropeptides in thymic, but not splenic, extracts. A single icv injection of IL-1beta increased contents of CRH, AVP, ACTH and beta-endorphin in the spleens of both sham-operated and adrenalectomised (ADX) rats. IL-1beta increased thymic contents of CRH and ACTH in sham-operated rats but these increases were not observed in ADX rats. These results suggest that the effects of IL-1beta on neuropeptide expression in the spleen are independent of glucocorticoids, whereas IL-1beta stimulation of neuropeptide expression in the thymus is dependent on circulating glucocorticoids. There were significant correlations between increases in CRH, ACTH and beta-endorphin in the spleen, and between CRH and ACTH in the thymus, consistent with the suggestion that IL-1beta-induced increases in ACTH and beta-endorphin may be mediated through CRH. These results provide evidence that stressors can directly influence neuropeptide expression in immune tissues. Thus stress may influence immune functions through paracrine mechanisms involving locally synthesised neuropeptides as well as through activation of the hypothalamo-pituitary-adrenal axis.