Importance of having agreeable friends in adolescence (especially when you are not)

Using the actor–partner interdependence model, we examined whether adolescent's agreeableness, best friend's agreeableness, and the interaction between adolescent‐friend agreeableness are important for interpersonal functioning. Adolescents (N = 158) in fifth to eighth grades who were part of best friend pairs completed personality and friendship measures. Adolescents' adjustment and victimization experiences were assessed by peer nominations. For boys, best friend's agreeableness moderated the relationship between the target boy's agreeableness and overt victimization, relational victimization, and externalizing problems. For girls, best friend's agreeableness moderated the relationship between the target girl's agreeableness and internalizing problems and prosocial skills. This study provides an initial glimpse into how traits of friends can influence outcomes beyond what would be expected from adolescents' personality alone.     

Interoceptive ability predicts aversion to losses

Emotions have been proposed to inform risky decision-making through the influence of affective physiological responses on subjective value. The ability to perceive internal body states, or “interoception” may influence this relationship. Here, we examined whether interoception predicts participants' degree of loss aversion, which has been previously linked to choice-related arousal responses. Participants performed both a heartbeat-detection task indexing interoception and a risky monetary decision-making task, from which loss aversion, risk attitudes and choice consistency were parametrically measured. Interoceptive ability correlated selectively with loss aversion and was unrelated to the other value parameters. This finding suggests that specific and separable component processes underlying valuation are shaped not only by our physiological responses, as shown in previous findings, but also by our interoceptive access to such signals.     

Psychometric properties of the Coping Strategy Indicator (CSI) in a study of coping behaviour amongst malawian students

Abstract

The Coping Strategy Indicator (CSI; Amirkhan 1990) is an inductively derived measure of responses to adverse circumstances. Although seeking to isolate “a few fundamental strategies with wide applicability” (Amirkhan 1990). the initial validation studies were all based on Californian populations. The present study repork findings from completion of the CSI by 415 Malawian students as part of their enrolment health check up. Factor analysis (principal components analysis with varimax rotation) identified three factors with very similar structure and loadings to those identified by Amirkhan, namely, Support Seeking, Problem Solving and Avoidance. As with the initial validation study, there was some evidence of withdrawal and distraction forming identifiable sub-components of Avoidance. The CSI does appear to provide a measure of core coping strategies which is robust across cultural settings, the theoretical implications of which are considered. The influence of factors such as age and gender on CSI scores is discussed     

Objective assessment of the functional role of spike train correlations using information measures

The functional role of correlations between neuronal spike trains remains strongly debated. This debate partly stems from the lack of a standardized analysis technique capable of accurately quantifying the role of correlations in stimulus encoding. We believe that information theoretic measures may represent an objective method for analysing the functional role of neuronal correlations. Here we show that information analysis of pairs of spike trains allows the information content present in the firing rate to be disambiguated from any extra information that may be present in the temporal relationships of the two spike trains. We validate and illustrate the method by applying it to simulated data with variable degrees of known synchrony, and by applying it to recordings from pairs of sites in the primary visual cortex of anaesthetized cats. We discuss the importance of information theoretic analysis in elucidating the neuronal mechanisms underlying object identification.     

Practice Effects on Motor Control in Healthy Seniors and Patients with Mild Cognitive Impairment and Alzheimer's Disease

ABSTRACT

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of “on-line” correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.