Endurance exercise selectively impairs prefrontal-dependent cognition

Two experiments are reported that examine the possibility that exercise selectively influences different types of cognition. To our knowledge, these experiments represent the first attempt to study higher-cognitive processes during exercise. Theoretical thinking was guided by the transient hypofrontality hypothesis. In both experiments, athletes who exercised at a sustained, moderate pace were compared to sedentary controls on two neuropsychological tests, one that is generally regarded as heavily dependent on prefrontal cognition and one that is relatively insensitive to prefrontal operation. Results showed that during exercise performance on tests demanding prefrontal-dependent cognition was impaired, while at the same time, cognitive processes requiring little prefrontal activity were unaffected.     

Anxiety sensitivity interacts with marijuana use in the prediction of anxiety symptoms and panic-related catastrophic thinking among daily tobacco users

The present investigation evaluated whether anxiety sensitivity interacted with marijuana use in relation to the prediction of panic-relevant variables among young adult tobacco smokers (n=265). Approximately 73% of the sample was composed of current marijuana smokers, with 78.5% of this sub-sample using marijuana more than once per week. As expected, after covarying cigarettes per day, alcohol use, and negative affectivity, the interaction between marijuana use and anxiety sensitivity predicted anxiety symptoms and agoraphobic cognitions. Partially consistent with prediction, the interaction between frequency of marijuana use and anxiety sensitivity predicted only anxiety symptoms. These results are discussed in relation to better understanding the potential role of regular marijuana use and anxiety sensitivity for panic-relevant emotional vulnerability among regular tobacco smokers.     

Psychometric evaluation of the Dutch version of the posttraumatic cognitions inventory (PTCI)

Trauma-related cognitions play an increasingly prominent role in research on trauma and in clinical practice. The present study investigated the psychometric characteristics of the Dutch version of the posttraumatic cognitions inventory (PTCI) and evaluated its potential as an outcome measure. Data were collected from a treatment-seeking sample of trauma victims (n=158) and a college sample (n=178). The PTCI's three-factor structure was retained in both samples. The PTCI demonstrated high internal consistency and two-week test-retest reliability. Convergent validity was evidenced by a pattern of correlations with instruments for trauma-related cognitions, posttraumatic stress disorder, and depressive symptoms that largely met a priori expectations. Reductions in self-reported and clinician-assessed posttraumatic stress disorder symptoms were positively associated with decreased PTCI scores, indicating that the PTCI could assist treatment evaluation. It is concluded that the Dutch version of the PTCI exhibits good psychometric characteristics and has the potential to contribute to trauma-related research.     

"I won't do what you tell me!": elevated mood and the assessment of advice-taking in euthymic bipolar I disorder

We hypothesized that when individuals with bipolar disorder are engaged in goal-directed behaviour and experience elevated mood, their decision-making becomes less constrained by advice from other people. This process may allow their goal-directed behaviour to persist, contributing to manic symptoms. Three groups of 32 participants: euthymic-bipolar-I, remitted-unipolar and never-depressed healthy controls were allocated to either a high or low mood induction. Advice-taking was assessed before and after the induction by a computerized task incorporating facial images. The bipolar group significantly opposed the advice given in the task after the high mood induction. The effect was specific to bipolar disorder and remained when controlling for possible confounds. Future work could investigate the effects of this process on manic symptoms, its origins, and the wider theoretical and clinical implications.     

Operationalizing the "vulnerability" and "stress" components of the hopelessness theory of depression: a multi-wave longitudinal study

The current study tested of the diathesis-stress component of the hopelessness theory (HT) using (1) a "weakest link" approach towards operationalizing vulnerability (e.g., an individual is as vulnerable to depression as his/her most depressogenic inferential style-DIS) and (2) an idiographic approach towards operationalizing high levels of stress. The procedure involved an initial assessment during which participants completed measures assessing DISs and depressive symptoms. The procedure also involved a series of eight follow-up assessments, occurring every 6 weeks, during which depressive symptoms and hassles were assessed. Hypotheses were tested in two samples of adults (i.e., adults diagnosed with a current MDE and adults diagnosed with a past MDE at Time 1). In line with hypotheses, in both samples, depressogenic weakest links were associated with greater elevations in depressive symptoms following elevations in hassles. At the same time, equally strong support was obtained for the HT when stress was operationalized from a nomothetic perspective and when vulnerability was operationalized as a DIS about causes (but not consequences or self).     

Attention Deficit-Hyperactivity Disorder, Depression, and Self- and Other-Assessments of Social Competence: A Developmental Study

This study examined whether others (i.e., teachers and parents) and self-appraisals of social competence mediated the relationship between Attention-Deficit/Hyperactivity Disorder (ADHD) and depression. To determine whether age moderated the effects of the mediation, the total sample was divided into younger (under 9) and older (at or above 9 years) age levels. The total sample (age range 6.6 to 11.7 years) was primarily male (194 boys and 52 females) and consisted of 148 children diagnosed with ADHD and 98 community controls. Three central findings were derived from this study. First, there was a strong relationship between ADHD (with and without comorbid ODD/CD) and depression in both younger and older aged children. Among younger children with ADHD, there was no differential influence on the level of depression depending on whether or not ADHD was comorbid with ODD/CD; in contrast, with older children, comorbid ODD/CD had higher levels of depression than was the case for children with ADHD that did not display such comorbidity. Second, with younger children approximately half of the relationship between ADHD (with and without comorbid ODD/CD) and depression was exclusively mediated by others appraisal of social competence. Third, a more complex relationship between ADHD and depression emerged during the later part of the childhood years. As such, the relationship between ADHD, others appraisals of social competence, and depression was further mediated by self-appraisals of social competence. Findings are discussed in terms of developmental theory and theoretical models of childhood depression.Rick Ostrander and David S. Crystal contributed equally to this article, and the order of authorship was determined by a coin toss.     

Perceived Control Mediates the Relation Between Parental Rejection and Youth Depression

Previous research suggests that both perceived parental control and rejection may be linked to youth depression. However, research has not definitively determined which dimension matters more, nor examined mediation within a clinical sample. We used a sample of clinically referred youth (aged 7-17) to determine (a) which parenting dimension is more closely associated with youth depression, and (b) whether youngsters' perceptions of control mediated the association. Perceived parental rejection was strongly linked to depressive symptoms (perceived parental control was not); youth perceived control did in fact mediate the association, and robustly so across gender and age groups. The findings suggest a developmental process in depression, plus potential foci for prevention and treatment programs.     

Reducing hopelessness: the interation of enhancing and depressogenic attributional styles for positive and negative life events among youth psychiatric inpatients

A recovery model of depression (Needles & Abramson, 1990 Journal of Abnormal Psychology, 99, 156-165) proposes that depressed individuals who exhibit an enhancing attributional style for positive events (i.e. make stable, global attributions) will be more likely to regain hopefulness and, thereby, recover from depression when positive events occur. While only a few studies have directly tested this model among clinical and nonclinical adult samples, none have tested a clinical sample of children and adolescents. Furthermore, prior studies testing this model have failed to examine the interactive role of an 'enhancing attributional style' for positive events with a 'depressogenic attributional style' for negative events, as prescribed by the hopelessness theory of depression (Abramson, Metalsky, & Alloy, 1989 Psychological Review, 96, 358-372). The current study presents data demonstrating that depressogenic and enhancing attributional styles interact to predict differential decreases in hopelessness. Implications of these findings and suggestions for future research also are presented.     

Self-Reported Depression Is Taxonic

Using the Sample-specific simulation method proposed by J. Ruscio, A. M. Ruscio, and T. M. Keane (2004), the S. R. H. Beach and N. Amir (2003) data are re-analyzed. The results for the MAXEIG and MAMBAC procedures are compared across simulated dimensional, simulated taxonic, and original distributions. The comparison indicates that depression is taxonic in the S. R. H. Beach and N. Amir (2003) sample but has a lower base (.06) than previously reported. This result indicates the need to use a relatively high cut point on total Beck Depression Inventory (i.e., BDI>21; A. T. Beck, 1978) when creating groups using the BDI. That is, the data support the presence of a discontinuity between “depressed” and “nondepressed” undergraduates at a relatively high level of depressive symptomatology. At the same time, it is noted that researchers should remain cautious about the interpretation of taxometric procedures used with low base rate taxa until they have been further investigated using Monte Carlo simulations.