Opportunistic propensity hinders commitment to acts in conditions of forced compliance and compliance without pressure

The psychosocial literature contains empirical evidence of the effects of personality variables on commitment to acts. The association of economic opportunism was explored with respect to postexperimental attitude change, intentions, and intrinsic motivation of individuals (N=132) toward acts with either forced compliance or compliance without pressure. In conditions of commitment and compliance without pressure, both intention and intrinsic motivation decreased as economic opportunism increased, while in conditions of commitment and forced compliance, intention increased as economic opportunism increased. Attitude change and economic opportunism did not appear to be associated in any experimental condition. These findings suggest that tendency to noncooperativeness predisposes to reduced concern for consistency and compliance with performed acts.     

Neuroanatomy and Neuropathology Associated with Korsakoff’s Syndrome

Although the neuropathology of Korsakoff's syndrome (KS) was first described well over a century ago and the characteristic brain pathology does not pose a diagnostic challenge to pathologists, there is still controversy over the neuroanatomical substrate of the distinctive memory impairment in these patients. Cohort studies of KS suggest a central role for the mammillary bodies and mediodorsal thalamus, and quantitative studies suggest additional damage to the anterior thalamus is required. Rare cases of KS caused by pathologies other than those of nutritional origin provide support for the role of the anterior thalamus and mammillary bodies. Taken together the evidence to date shows that damage to the thalamus and hypothalamus is required, in particular the anterior thalamic nucleus and the medial mammillary nucleus of the hypothalamus. As these nuclei form part of wider memory circuits, damage to the inter-connecting white matter tracts can also result in a similar deficit as direct damage to the nuclei. Although these nuclei and their connections appear to be the primary site of damage, input from other brain regions within the circuits, such as the frontal cortex and hippocampus, or more distant regions, including the cerebellum and amygdala, may have a modulatory role on memory function. Further studies to confirm the precise site(s) and extend of brain damage necessary for the memory impairment of KS are required.     

Consolidation and translation regulation

mRNA translation, or protein synthesis, is a major component of the transformation of the genetic code into any cellular activity. This complicated, multistep process is divided into three phases: initiation, elongation, and termination. Initiation is the step at which the ribosome is recruited to the mRNA, and is regarded as the major rate-limiting step in translation, while elongation consists of the elongation of the polypeptide chain; both steps are frequent targets for regulation, which is defined as a change in the rate of translation of an mRNA per unit time. In the normal brain, control of translation is a key mechanism for regulation of memory and synaptic plasticity consolidation, i.e., the off-line processing of acquired information. These regulation processes may differ between different brain structures or neuronal populations. Moreover, dysregulation of translation leads to pathological brain function such as memory impairment. Both normal and abnormal function of the translation machinery is believed to lead to translational up-regulation or down-regulation of a subset of mRNAs. However, the identification of these newly synthesized proteins and determination of the rates of protein synthesis or degradation taking place in different neuronal types and compartments at different time points in the brain demand new proteomic methods and system biology approaches. Here, we discuss in detail the relationship between translation regulation and memory or synaptic plasticity consolidation while focusing on a model of cortical-dependent taste learning task and hippocampal-dependent plasticity. In addition, we describe a novel systems biology perspective to better describe consolidation.     

The heat of transport of vacancies in solid argon

Abstract

Computer simulations of the motion of vacancies in a Lennard-Jones model of solid argon have been made by the molecular dynamics technique. The results have been used to evaluate and analyse the heat of transport parameter Q*v for vacancies in this substance. At a temperature of 30 K it is found to be -12 kJ mol-1. The theory of transport shows that there are three main contributions to this quantity coming from the fluxes of kinetic energy, potential energy and a virial of the forces related to the local stress tensor. The main contribution to Q*v is found to be that from the virial term. This explains why discussions that aim to relate the heat of transport to the corresponding enthalpy of activation (which is almost entirely potential energy) have not been successful.     

Correlates and phenomenology of first and third person memories

Worry as a trait is an individual's general tendency to become worried, which in severe cases is associated with the diagnosis Generalised Anxiety Disorder. Mental time travel (MTT) is the ability to mentally project oneself into one's personal past or future, in terms of memories of personal past events or projections of possible events in the personal future. MTT can be voluntarily initiated or occur involuntarily. The current exploratory study investigated involuntary and voluntary MTT in the context of trait worry, thereby bringing together research on worry and MTT. High (N=20) and low (N=16) worriers recorded involuntary and voluntary autobiographical memories and future projections using a structured diary method. We predicted that MTT in high worriers would show signs of cognitive avoidance, such as reduced emotional intensity, more observer perspective, less visual imagery, or coming up with overgeneral or less self-relevant events. We found only partial support for our hypotheses in that high worriers rated personal memories and future projections lower on measures of self-relevance than did low worriers.     

Short report: The impact of measurement conditions on the validity of self-assessment in a selection setting

Two experimental studies investigated the impact of format and instructions on the validity of SAs, using participants applying for junior management positions in a public sector organization. In Study 1 (607 participants) self-assessments (SAs) were valid when applicants rated overall competencies or the same competencies broken down into discrete elements, but not when providing behavioural evidence prior to rating competencies. The effect of social comparison instructions was also explored but found to have no impact on validity. Study 2 used a subset of 193 candidates from the previous study who attended the next stage of the selection process. Consistent with predictions it was found that unbalanced, positively toned scales were more valid than conventional scales, and highest validities were achieved when used with instructions requesting a realistic SA of strengths and weaknesses. Interestingly, gender differences were found in both studies. These findings are discussed in terms of their implications for both research and practice.     

Undifferentiated facial electromyography responses to dynamic,audio‐visual emotion displays in individuals with autism spectrum disorders

We examined facial electromyography (fEMG) activity to dynamic, audio‐visual emotional displays in individuals with autism spectrum disorders (ASD) and typically developing (TD) individuals. Participants viewed clips of happy, angry, and fearful displays that contained both facial expression and affective prosody while surface electrodes measured corrugator supercilli and zygomaticus major facial muscle activity. Across measures of average and peak activity, the TD group demonstrated emotion‐selective fEMG responding, with greater relative activation of the zygomatic to happy stimuli and greater relative activation of the corrugator to fearful stimuli. In contrast, the ASD group largely showed no significant differences between zygomatic and corrugator activity across these emotions. There were no group differences in the magnitude and timing of fEMG response in the muscle congruent to the stimuli. This evidence that fEMG responses in ASD are undifferentiated with respect to the valence of the stimulus is discussed in light of potential underlying neurobiological mechanisms.     

Conditional estimation of exponential random graph models from snowball sampling designs

A complete survey of a network in a large population may be prohibitively difficult and costly. So it is important to estimate models for networks using data from various network sampling designs, such as link-tracing designs. We focus here on snowball sampling designs, designs in which the members of an initial sample of network members are asked to nominate their network partners, their network partners are then traced and asked to nominate their network partners, and so on. We assume an exponential random graph model (ERGM) of a particular parametric form and outline a conditional maximum likelihood estimation procedure for obtaining estimates of ERGM parameters. This procedure is intended to complement the likelihood approach developed by  Handcock and Gile (2010) by providing a practical means of estimation when the size of the complete network is unknown and/or the complete network is very large. We report the outcome of a simulation study with a known model designed to assess the impact of initial sample size, population size, and number of sampling waves on properties of the estimates. We conclude with a discussion of the potential applications and further developments of the approach.     

Goal and personality trait development in emerging adulthood

The present research examined continuity and change in the importance of major life goals and the relation between change in goals and change in personality traits over the course of college (N = 298). Participants rated the importance of their life goals 6 times over a 4-year period and completed a measure of the Big Five personality traits at the beginning and end of college. Like personality traits, life goals demonstrated high levels of rank-order stability. Unlike personality traits assessed during the same period and in the same sample, the mean importance of most life goals decreased over time. Moreover, each goal domain was marked by significant individual differences in change, and these individual differences were related to changes in personality traits. These findings provide insights into the relatively unstudied question of how life goals change during emerging adulthood.     

Reconceptualizing individual differences in self-enhancement bias: an interpersonal approach

Self-enhancement bias has been studied from 2 perspectives: L. Festinger's (1954) social comparison theory (self-enhancers perceive themselves more positively than they perceive others) and G. W. Allport's (1937) self-insight theory (self-enhancers perceive themselves more positively than they are perceived by others). These 2 perspectives are theoretically and empirically distinct, and the failure to recognize their differences has led to a protracted debate. A new interpersonal approach to self-enhancement decomposes self-perception into 3 components: perceiver effect, target effect, and unique self-perception. Both theoretical derivations and an illustrative study suggest that this resulting measure of self-enhancement is less confounded by unwanted components of interpersonal perception than previous social comparison and self-insight measures. Findings help reconcile conflicting views about whether self-enhancement is adaptive or maladaptive.