Different mechanisms of fear extinction dependent on length of time since fear acquisition

Fear extinction is defined as a decline in conditioned fear responses (CRs) following nonreinforced exposure to a feared conditioned stimulus (CS). Behavioral evidence indicates that extinction is a form of inhibitory learning: Extinguished fear responses reappear with the passage of time (spontaneous recovery), a shift of context (renewal), and unsignaled presentations of the unconditioned stimulus (reinstatement). However, there also is evidence to suggest that extinction is an "unlearning" process corresponding to depotentiation of potentiated synapses within the amygdala. Because depotentiation is induced more readily at short intervals following LTP induction and is not inducible at all at a sufficient delay, it may be that extinction initiated shortly following fear acquisition preferentially engages depotentiation/"unlearning," whereas extinction initiated at longer delays recruits a different mechanism. We investigated this possibility through a series of behavioral experiments examining the recoverability of conditioned fear following extinction. Consistent with an inhibitory learning mechanism of extinction, rats extinguished 24-72 h following acquisition exhibited moderate to strong reinstatement, renewal, and spontaneous recovery. In contrast, and consistent with an erasure mechanism, rats extinguished 10 min to 1 h after acquisition exhibited little or no reinstatement, renewal, or spontaneous recovery. These data support a model in which different neural mechanisms are recruited depending on the temporal delay of fear extinction.     

Integrating incremental learning and episodic memory models of the hippocampal region

By integrating previous computational models of corticohippocampal function, the authors develop and test a unified theory of the neural substrates of familiarity, recollection, and classical conditioning. This approach integrates models from 2 traditions of hippocampal modeling, those of episodic memory and incremental learning, by drawing on an earlier mathematical model of conditioning, SOP (A. Wagner, 1981). The model describes how a familiarity signal may arise from parahippocampal cortices, giving a novel explanation for the finding that the neural response to a stimulus in these regions decreases with increasing stimulus familiarity. Recollection is ascribed to the hippocampus proper. It is shown how the properties of episodic representations in the neocortex, parahippocampal gyrus, and hippocampus proper may explain phenomena in classical conditioning. The model reproduces the effects of hippocampal, septal, and broad hippocampal region lesions on contextual modulation of classical conditioning, blocking, learned irrelevance, and latent inhibition.     

Do readers make inferences about conversational topics?

When we read that two protagonists in a story chatted together for a couple of minutes, do we draw inferences about the topic of the conversation on the basis of information presented earlier in the text? Participants read passages in which protagonists part and later reunite; the passages ended with a sentence either that implied conversation or did not. In Experiment 1, participants' continuation sentences indicated that inferences about the topic of conversation were drawn. Recognition probe data in Experiment 2 provided more immediate evidence of such inferences. Experiment 3 addressed a possible confound in Experiment 2 and again provided evidence that readers inferred the continuation of the conversation. In Experiments 4 and 5, we investigated the effect of having the targeted conversational topic be a secret that should not be shared between the protagonists. The results are discussed in terms of the collaboration between passive, memory-based text processing and schema-driven comprehension processes.     

Training Parents in Forgiving and Reconciling

Teaching parents how to forgive transgressions of parenting partners may reduce negative emotions, increase positive emotions, and, thus, decrease parenting stress. We implemented a waiting-list design to investigate the efficacy of a 9-hour psychoeducational group intervention, Forgiveness and Reconciliation through Experiencing Empathy (FREE), presented to 27 parents and caregivers of children 0–9 years old. Participants receiving FREE exhibited increased forgiveness of a target offense by the parenting partner and increased forgiveness of all parenting offenses. This study offers initial evidence that an intervention to promote forgiveness and reconciliation in parents could be beneficial and might improve parenting relations.     

Emotional information processing in repressors: The vigilance–avoidance theory

A vigilance–avoidance theory of the repressive coping style (low trait anxiety and high defensiveness) is presented. The new theory attempts to account for several key findings, including the discrepancy between low self-reported anxiety and high behavioural and physiological indicators of anxiety shown by individuals with a repressive coping style. According to the theory, repressors have an initial rapid vigilant response triggering behavioural and physiological responses and involving attentional and interpretive biases to self-relevant threat stimuli. These biases may be based on negative self-relevant schematic information. This initial vigilant stage is followed by an avoidance stage involving avoidant cognitive biases (attentional, interpretive, and memory) that inhibit the conscious experience of anxiety. Future research should examine systematically the time course of repressors’ reactions to threatening and non-threatening stimuli.     

Natural scene statistics mediate the perception of image complexity

Humans are sensitive to complexity and regularity in patterns (Falk & Konold, 1997; Yamada, Kawabe, & Miyazaki, 2013). The subjective perception of pattern complexity is correlated to algorithmic (or Kolmogorov-Chaitin) complexity as defined in computer science (Li & Vitányi, 2008), but also to the frequency of naturally occurring patterns (Hsu, Griffiths, & Schreiber, 2010). However, the possible mediational role of natural frequencies in the perception of algorithmic complexity remains unclear. Here we reanalyze Hsu et al. (2010) through a mediational analysis, and complement their results in a new experiment. We conclude that human perception of complexity seems partly shaped by natural scenes statistics, thereby establishing a link between the perception of complexity and the effect of natural scene statistics.     

Identifying repressors: A methodological issue for health psychology

Abstract

The majority of studies in health psychology use self-report measures. However, there is a growing body of evidence indicating that this methodology may be problematic for a significant minority of the population: individuals who possess a repressive coping style (repressors). Repressors, who fail to report negative affect, answer many self-report measures in a positive fashion. Research has identified an association between repressors, who are identified by low trait anxiety scores and high defensiveness scores, and adverse health outcomes. Therefore, repressors are an important group for health psychologists to investigate. Health psychology research should use more than one method of data collection in an attempt to unravel this difficult methodological problem.     

Predicting Burnout Among HIV/AIDS and Oncology Health Care Workers

Abstract

This study examined the relationship between repressive coping, controllability, self-esteem and comparative optimism for health-related events. Repressors (low trait anxiety-high defensiveness) compared with both (a) specific control groups on anxiety and defensiveness (e.g., low-anxious, high-anxious and defensive high anxious) and (b) total nonrepressors were significantly more comparatively optimistic for health-related events. Repressors remained significantly more comparatively optimistic than total nonrepressors when self-esteem was partialled out.

For individual events, repressors differed in comparative optimism for events which were rated as high controllability. It is concluded that repressors are exhibiting comparative optimism over and above nonrepressor groups for events which are rated as controllable. These results suggest that comparative optimism findings may be exaggerated by not controlling for the disproportionate influence of repressors in skewing sample means. Suggestions for future studies are discussed.     

Illness perceptions and self efficacy beliefs in adolescents and young adults with insulin dependent diabetes mellitus

Abstract

The study examined the role of illness perceptions and self-efficacy in diabetic regimen adherence and metabolic control among young patients with Insulin Dependent Diabetes Mellitus (IDDM). Sixty-four outpatients with Insulin Dependent Diabetes completed measures of illness perceptions, generalised and diabetes specific self-efficacy and a self-report measure of adherence. Metabolic control (HbAlc) was also assessed. Control, identity and consequences components of illness perceptions were significantly correlated with self-efficacy expectancies. Control beliefs were consistently associated with self-reported adherence across all treatment aspects and accounted for 39% of the predicted variance in total adherence. The associations of the other psychological predictors examined, varied depending on the regimen area. Multiple regression analysis showed that 30.8% of the variance in HbAlc assays was explained by patients' diabetes specific self-efficacy, consequences and identity. Our findings suggest that patients' beliefs are useful predictors of physiological and behavioural outcomes in diabetes self-management and should thus be the focus of routine clinical assessments and future interventions.     

A Longitudinal Comparison of Posttraumatic Stress Disorder and Depression Among Military Service Components

The purpose of this study was to longitudinally investigate PTSD and depression between Reserve, National Guard, and active duty continuously and dichotomously. The study consisted of Millennium Cohort Study participants and used self-reported symptoms. Repeated measures modeling assessed PTSD and depression continuously and dichotomously over time. A subanalysis among only recently deployed personnel was conducted. Of the 52,653 participants for the PTSD analysis, the adjusted PCL-C means were 34.6 for Reservists, 34.4 for National Guardsmen, and 34.7 for active duty members, respectively. Of the 53,073 participants for depression analysis, the adjusted PHQ-9 means were 6.8, 6.7, and 7.2, respectively. In dichotomous models, Reservists and National Guardsmen did not have a higher risk of PTSD or depression compared with active duty members. Among deployers, Reservists and National Guardsmen had higher odds (odds ratio = 1.16, 95% confidence limit [CL] [1.01, 1.34] and OR = 1.19, 95% CL [1.04, 1.36], respectively) of screening positive for PTSD, but not depression. Although Reserve and National Guard deployers had modestly increased odds of PTSD compared with active duty members, overall there were minimal differences in the risk and symptom scores of PTSD and depression between service components.