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.     

ASSOCIATIVE PROCESSES IN FALSE RECALL AND FALSE RECOGNITION

Abstract— Studying a list of words associated to a critical nonpresented word results in high rates of false recall and false recognition for that nonpresented item (Roediger & McDermott, 1995) Two experiments examined the effect of manipulating the number of associates presented on false recall and later false recognition of a nonpresented item. In Experiment 1, associate lists of varying lengths were studied, in Experiment 2, list length was held constant and the number of associates within the list was manipulated. In both experiments, the rate of critical intrusions in recall increased steadily with increasing number of associates studied Most notably, the filler words used in Experiment 2 to equate the list lengths did not affect the rate of critical intrusions, although they did depress recall of studied words. False recall and false recognition appear to be tied to the total, not the mean, associative strength of items in the list.     

Cognitive sequelae of repeated head injury in a population of intravenous drug users

The relationship between closed head injury and performance on neuropsychological (NP) tests was investigated in a group of intravenous drug users (IVDUs). Subjects with repeated head traumas involving loss of consciousness (LOC) performed worse than both a control group without LOC and reference group with only a single episode of LOC. There were no significant differences between the last two groups. Performance on tests of memory, attention, and motor performance was significantly worse in the group with repeated head injury. The average time since the last episode of LOC was more than 11 years. We conclude from these findings that a single episode of LOC does not result in significant cognitive impairment in this population. Two or more episodes, however, are more likely to produce chronic cognitive impairment.     

Promotion and employee turnover: Critique,meta-analysis,and implications

Qualitative reviews of the withdrawal literature have reached inconsistent conclusions regarding the strength of the relationship between promotion and turnover. Several issues were addressed in this study which may account for these inconsistencies. First, we differentiate among three distinct operationalizations of promotion: (1) promotion satisfaction; (2) perceptions of promotional opportunity; and (3) actual promotion. We then conduct quantitative reviews using meta-analytic procedures on turnover and the three operationalizations of promotion. We found no significant relationships between promotion satisfaction and turnoveror between perceived promotional opportunities and turnover. However, a significant negative relationship was found between actual promotion and turnover. Theoretical implication of these findings are presented.     

Preparing the Way: A Qualitative Study of High-Achieving African American Males and the Role of the Family

Employed qualitative methods to examine the role of the family in the academic success of very high-achieving African American males. Findings revealed a complex tapestry of family processes and contexts involved in each youth's journey to outstanding academic achievement. Specifically, the combined importance of parental-determined academic engagement, strict discipline, nurturance, and community connectedness appeared to counteract potentially negative contextual influences of neighborhood, peers, schools, and society. The qualitative findings tell a multifaceted, rich, and compelling story of the pathways to academic success for Black males, and highlight the need for culture-specific and ecologically based conceptualization, research, and intervention approaches.     

The Impact of Sex and Gender Role Self-Perception on Affective Reactions to Different Types of Film

To what extent do differences in biologicalsexand psychological gender identity influence affectivereactions to different genres of film? In order toaddress this question, this investigation examined the impact of sex and gender roleself-perceptions on viewers' responses to neutral,melodramatic, and violent film segments. Working with apredominantly Caucasian population (93% Caucasian) at asoutheastern university, the results emphasize theimportance of sex and gender role self-perceptions onviewers' affective responses to media entertainment. Theimplications of these findings are discussed.

     

Prevalence of ADHD and comorbid disorders among elementary school children screened for disruptive behavior

In the context of a school-based prevention of conduct disorder program, 7,231 first- through fourth-grade children were screened for cross-setting disruptive behavior. Frequencies of DSM-III-R psychiatric disorders and patterns of comorbidity were assessed. We also examined the association of psychiatric diagnosis with child and parent characteristics to determine differential risk based on diagnostic subgroups. Attention deficit hyperactivity disorder (ADHD) and oppositional-defiant disorder (ODD) were the most frequent diagnoses. Mood and anxiety disorders were infrequent as single diagnoses. Patterns of comorbidity demonstrated that both externalizing and internalizing disorders commonly cooccurred with ADHD. More severe degrees of psychopathology and psychosocial risk accrued to the subgroup of youths with ADHD plus a comorbid externalizing disorder.This study was supported by grant MN-46584 from the National Institute of Mental Health.     

Academic Gender Bias and Women's Behavioral Agency Self-Efficacy

The relationship between academic gender bias and female students' agentic self-efficacy expectations was examined. Agentic self-efficacy expectations was defined as an individual's beliefs about her ability to successfully engage in proactive educational and career facilitative behaviors. Participants included 67 full-time junior and senior undergraduate women enrolled in traditional, nontraditional, and gender-neutral majors. Results revealed that perceived academic gender bias was significantly predictive of agentic self-efficacy expectations, above and beyond the contributions of sex role attitudes, gender concentration of major, and race/ethnicity. Implications for women's career development and future research are discussed.     

The effects of situational performance constraints on intrinsic motivation and satisfaction: The role of perceived competence and self-determination

Situational performance constraints, task interest, and pay contingencies were manipulated in a laboratory study in order to investigate the cognitive mechanisms associated with the previously observed detrimental effects of constraints on affective task reactions. It was hypothesized that feelings of task competence and self-determination would account for both the direct and the interactive effects of constraints on motivation and satisfaction. The results of the study indicated that despite the fact that participants' performance was being constrained and they were aware of these constraints, the mere presence of the constraints alone failed to result in lower levels of satisfaction or motivation on a proofreading task. Post hoc analyses suggested that the constraints, in fact, led to negative affective task reactions when they also reduced participants' feelings of competence and self-determination. Interestingly, participants' generalized locus of control was associated with such effects. Internals tended to maintain stronger feelings of competence and self-determination than externals in the presence of constraints, thereby also maintaining greater motivation and satisfaction.