Broadening of activity with flow across neural structures

Synfire chains have long been suggested as a substrate for perception and information processing in the nervous system. However, embedding activation chains in a densely connected nervous matrix risks spread of signal that will obscure or obliterate the message. We used computer modeling and physiological measurements in rat hippocampus to assess this problem of activity broadening. We simulated a series of neural modules with feedforward propagation and random connectivity within each module and from one module to the next. We found that activity broadened as it propagated from one module to the next. This occurred over a wide array of parameters with greater broadening seen with increasing excitatory-excitatory synaptic strength. Activity broadening correlated positively with propagation velocity. Multi-electrode measurements of activity propagation in disinhibited CA1 slice demonstrated broadening of about 50% over 1 mm. Such broadening is a problem for information transfer that must be dealt with in a fully functioning nervous system.     

Regret resolution, aging, and adapting to loss

Both theory and empirical evidence suggest that people who have unresolved regrets experience lower levels of well-being than do those who resolve their regrets. In this study, the authors examined the role of regret resolution during bereavement by assessing whether (a) regret resolution would aid in adapting to the death of a loved one and (b) older adults would be more successful at resolving their bereavement-related regrets than would younger adults. Mixed models were run with longitudinal data from an age-heterogeneous sample of 147 men and women who were eventually bereaved after providing care for a loved one through a hospice. As expected, regret resolution contributed to adjustment as indicated by postloss patterns of depressive symptoms, well-being, and rumination; further, older adults were more likely to resolve their regrets than were younger adults. Implications for encouraging regret resolution early in bereavement are discussed.     

Affective theory of mind inferences contextually influence the recognition of emotional facial expressions

The recognition of emotional facial expressions is often subject to contextual influence, particularly when the face and the context convey similar emotions. We investigated whether spontaneous, incidental affective theory of mind inferences made while reading vignettes describing social situations would produce context effects on the identification of same-valenced emotions (Experiment 1) as well as differently-valenced emotions (Experiment 2) conveyed by subsequently presented faces. Crucially, we found an effect of context on reaction times in both experiments while, in line with previous work, we found evidence for a context effect on accuracy only in Experiment 1. This demonstrates that affective theory of mind inferences made at the pragmatic level of a text can automatically, contextually influence the perceptual processing of emotional facial expressions in a separate task even when those emotions are of a distinctive valence. Thus, our novel findings suggest that language acts as a contextual influence to the recognition of emotional facial expressions for both same and different valences.     

Increased sensitivity to the disinhibiting effects of alcohol in binge drinkers.

Heavy episodic alcohol use, or binge drinking, is a serious public health problem. Binge drinking is endemic in college students and has resulted in numerous alcohol-related tragedies, including acute alcohol poisonings, falls, and automobile collisions. Such negative outcomes might occur because binge drinkers are generally more impulsive, and this impulsivity might be exacerbated under alcohol. The purpose of this study was to examine this hypothesis by comparing the acute effects of alcohol on a cognitive measure of behavioral control in binge and nonbinge drinkers. The results indicated that binge drinkers act more impulsively and report feeling more stimulated under an acute 0.65 g/kg dose of alcohol compared to nonbinge drinkers. The present finding of a heightened disinhibitory reaction to alcohol in binge drinkers may help explain the link between impulsivity and problem drinking at a more fundamental level of behavioral control.     

Experiential avoidance and aversive visual images: response delays and event-related potentials on a simple matching task

In Experiment 1, participants high (n=15) or low in avoidance (n=14), as measured by the Acceptance and Action Questionnaire, completed a simple matching task that required them to choose whether or not to look at an aversive visual image. Only the high-avoidance participants took longer to emit a correct response that produced an aversive rather than a neutral picture. Additionally, the high-avoiders reported greater levels of anxiety following the experiment even though they rated the aversive images as less unpleasant and less emotionally arousing than their low-avoidant counterparts. In Experiment 2, three groups, representing high-, mid- and low-avoidance (n=6 in each) repeated the matching task with the additional recording of event-related potentials (ERPs). The findings of Experiment 1 were replicated in terms of reaction times and subjective ratings. The ERPs confirmed that the participants attended to the content of the images and differentiated between the aversive and neutral image types. The ERPs also showed significantly greater negativity for electrodes over the left hemisphere relative to the midline for only the high-experiential avoidance (EA) group. Given the left hemisphere dominance for language, the data suggest that the high-EA group engaged in verbal strategies to regulate their emotional responses.     

Exploring how constraints created by other people influence intraindividual variation in objective performance measures

Objective performance indicators have low test-retest reliability, particularly in complex jobs. Yet, little is actually known about the reasons why objective performance indicators lack temporal stability. The authors address this issue by using data from a sample of 106 professional football players to explore how the actions of other people influence intraindividual variation in performance. Results suggest that weekly measures of performance outcome exhibit substantial variability within individuals. A significant portion of this within-person variance is explained by environmental fluctuation created by the constraining actions of other people. Individuals with highly fluctuating past performance exhibit stronger relationships between the actions of competitors and subsequent performance outcomes. The intraindividual relationship between fluctuating constraints and performance outcomes is also stronger for individuals in more complex jobs.     

Robust dimensions of anxiety sensitivity: development and initial validation of the Anxiety Sensitivity Index-3

Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n=2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n=4,494) and a clinical sample from the United States and Canada (n=390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI.     

Childhood anxiety sensitivity index factors predict unique variance in DSM-IV anxiety disorder symptoms

Anxiety sensitivity (AS) is an established cognitive risk factor for anxiety disorders. In children and adolescents, AS is usually measured with the Childhood Anxiety Sensitivity Index (CASI). Factor analytic studies suggest that the CASI is comprised of 3 lower-order factors pertaining to Physical, Psychological and Social Concerns. There has been little research on the validity of these lower-order factors. We examined the concurrent and incremental validity of the CASI and its lower-order factors in a non-clinical sample of 349 children and adolescents. CASI scores predicted symptoms of DSM-IV anxiety disorder subtypes as measured by the Spence Children's Anxiety Scale (SCAS) after accounting for variance due to State-Trait Anxiety Inventory scores. CASI Physical Concerns scores incrementally predicted scores on each of the SCAS scales, whereas scores on the Social and Psychological Concerns subscales incrementally predicted scores on conceptually related symptom scales (e.g. CASI Social Concerns scores predicted Social Phobia symptoms). Overall, this study demonstrates that there is added value in measuring AS factors in children and adolescents.