Acute inhibition of calcineurin restores associative learning and memory in Tg2576 APP transgenic mice

Misfolded amyloid beta peptide (Abeta) is a pathological hallmark of Alzheimer's disease (AD), a neurodegenerative illness characterized by cognitive deficits and neuronal loss. Transgenic mouse models of Abeta over-production indicate that Abeta-induced cognitive deficits occur in the absence of overt neuronal death, suggesting that while extensive neuronal death may be associated with later stages of the human disease, subtle physiological changes may underlie initial cognitive deficits. Therefore, identifying signaling elements involved in those Abeta-induced cognitive impairments that occur prior to loss of neurons may reveal new potential pharmacological targets. Here, we report that the enzymatic activity of calcineurin, a key protein phosphatase involved in phosphorylation-dependent kinase activity crucial for synaptic plasticity and memory function, is upregulated in the CNS of the Tg2576 animal model for Abeta over-production. Furthermore, acute treatment of Tg2576 mice with the calcineurin inhibitor FK506 (10mg/kg i.p.) improves memory function. These results indicate that calcineurin may mediate some of the cognitive effects of excess Abeta such that inhibition of calcineurin shall be further explored as a potential treatment to reverse cognitive impairments in AD.     

Methamphetamine abuse and impairment of social functioning: a review of the underlying neurophysiological causes and behavioral implications

The highly addictive drug methamphetamine has been associated with impairments in social cognitions as evidenced by changes in users' behaviors. Physiological changes in brain structure and functioning, particularly in the frontal lobe, have also been identified. The authors propose a biopsychosocial approach to understanding the effects of methamphetamine addiction by relating the physiological effects of the drug to the behaviors and social cognitions of its users, through the application of the theory of mind paradigm. Although onset of methamphetamine use has been linked to the desire for socialization, chronic use has been associated with an increase in depression, aggressiveness, and social isolation, behaviors that also implicate involvement of the frontal lobe. The reviewed literature provides strong circumstantial evidence that social-cognitive functioning is significantly impacted by methamphetamine use and that the social isolation, depression, and aggressiveness associated with chronic use is due to more than just the social withdrawal associated with addiction. Treatment considerations for methamphetamine must therefore consider the role of social cognition, and pharmacological responses must address the documented impact of the drug on frontal lobe functioning.     

Personality factors related to quantitative estimation skill: confirmation and extension

The relationships of two measures of quantitative estimation skill, computational estimation and numerosity estimation, were examined with the 16 PF Global Factors corresponding to the Big Five personality dimensions in a sample of 80 college students. Correlations of Computational Estimation with the 16 PF scores confirmed findings from a previous study which used the NEO-Five Factor Inventory as a measure of the Big Five, specifically showing that Computational Estimation correlated significantly with the 16 PF's Independence factor. Numerosity Estimation did not correlate significantly with any of the 16 PF Global Factors or with any of the ability measures (Computational Estimation, SAT Verbal, SAT Mathematics, and self-rated mathematics ability) used in the study.     

Sense, nonsense, and the use of personality measures

Criticize measurement-based personality research by recounting a well-known limitation: indices of relationship are often inflated because of the similarity of content across measures of presumably different constructs. In this paper we endorse the major contention of Nicholls et al. that measurement-based research may be conducted thoughtlessly, and we extend their thinking by pointing out an important underlying issue—the problem of defining what constitutes a “syndrome.” In contrast to them, however, we argue that the problems in measurement they cite do not entail the consequences they foresee and, in addition, have limited application.     

Psychometric analysis of five measures of spatial ability

This study analyzed psychometric properties of five measures of spatial ability on 96 young adults, with supplementary analysis for three of the measures on another sample of 71 young adults. Two measures were taken from the widely cited Kit of Factor-Referenced Cognitive Tests and three other measures were taken from a relatively new source originally intended as laboratory demonstrations. Previous research provided limited information on the psychometric properties of the measures. All five measures yielded adequate reliability and loaded on a single factor. Three measures yielded markedly skewed distributions. Two measures showed clear sex differences with men scoring higher but this difference seemed contaminated by a speed factor; three measures did not show a sex difference. Recommendations for use of the measures in future studies are provided.     

Negative cognitive styles, dysfunctional attitudes, and the remitted depression paradigm: a search for the elusive cognitive vulnerability to depression factor among remitted depressives

Results from studies using a behavioral high-risk design and approximations to it generally have corroborated the cognitive vulnerability hypothesis of depression, whereas results from remitted depression studies typically have not. Suspecting that design features of previously conducted remitted designs likely precluded them from detecting maladaptive cognitive patterns, the authors conducted a study featuring the remitted design that has been successful in studies of a biological vulnerability for depression. Participants' current depressive symptoms, negative cognitive styles (hopelessness theory), dysfunctional attitudes (Beck's theory), and lifetime prevalence of clinically significant depression were assessed. Participants who had remitted from an episode of clinically significant depression had more negative cognitive styles, but not greater levels of dysfunctional attitudes, than did never depressed individuals.     

Stressors and Stress Reactions Among University Personnel

A large, ethnically diverse, and representative sample of university workers in administrative, instructional, and blue-collar/clerical support categories were administered a battery of questionnaires designed to assess job and nonwork stress, biopsychosocial reactions to stress, emotionality, medical symptoms and utilization, and perceived social support, among other variables. A total of 831 participants returned questionnaires. The principal results showed that job and nonwork stress correlated positively with behavioral, cognitive, and physiological reactions to stress as well as with negative emotionality. Job and nonwork stress correlated meaningfully with medical symptoms; nonwork stress also correlated at a useful level with reported medical utilization. Social support did not generally modulate reports of stress or reactions to stress. It was also found that support staff reported higher levels of nonwork stress and lower levels of work stress, but that 2 measures of job stress did not differentiate administrative and instructional personnel. Younger staff reported higher levels of job and nonwork stress, and females reported higher levels of nonwork stress, irrespective of job category. The results were discussed in terms of their importance for understanding the nature of stress among personnel on the university campus and in relation to prior research.     

On-line computerized career guidance

The background, rationale, and development of an on-line computerized career guidance system are presented. Special emphasis is placed on the relationship between the conceptual theory and the working design for the system.     

Learning to find the opponent: an ethological analysis of the behavior of paradise fish (Macropodus opercularis) in intra- and interspecific encounters.

In Experiment 1, 15 behavior patterns of male paradise fish (Macropodus opercularis; n = 72) toward a male conspecific, a male of another species, or no stimulus were recorded, both in home and novel situations. In Experiment 2, the same behaviors were recorded in a runway, and the same stimuli were used as reinforcers in the goal box (n = 18). A typical learning curve was seen when the subject found a male paradise fish in the goal box, learning was followed by apparent extinction when another species was found in the goal box, and few signs of learning were seen when the goal box was empty. Performance of the fish in both experiments can be accounted for by a strong aggressive motivation, a less strong but clear general curiosity, and habituation to the experimental procedure. In contrast to recent assertions in the literature, we conclude that aggressive behavior clearly can serve as a reinforcer in an instrumental learning situation.