Analysis of the US-preexposure effect in flavor acceptance conditioning

In three experiments, rats received exposure to a sucrose solution followed by conditioning with a neutral flavor as the conditioned stimulus (CS) and sucrose as the unconditioned stimulus (US). In Experiments 1 and 2, some rats were given both the preexposure and the conditioning phases in a highly familiar context (the homecage), whereas other animals received both phases in a novel and distinctive context. In both cases the magnitude of the conditioning effect was reduced by preexposure to the US. Experiment 3 directly assessed the possible role of contextual cues by changing the context between the exposure phase and the conditioning phase but found no loss of the US-preexposure effect in these conditions. These results lend no support to the blocking-by-context account of the US-preexposure effect; alternative interpretations are considered.     

The Big-Five, sense of control, mental health and fear of crime as contributory factors to attitudes towards punishment

Low sense of control (SoC), mental health problems and fear of crime (FoC) have separately and previously been linked to the Big-Five personality dimensions, but no study to date has sought to integrate these constructs simultaneously in relation to overall punitiveness. These constructs were assessed in 232 participants using an online survey to examine hypothesised relations between FoC and SoC, poorer mental health, Neuroticism (N), Extraversion (E) and Conscientiousness (C), and any resultant punitiveness. Measures were highly correlated, and an exploratory factor analysis summarised these as ‘instability’ and ‘crime attitude’ dimensions. A structural equation model found that high levels of N and poor mental health, as well as low levels of C, E and SoC were related to a latent variable of ‘distress’, which fed into heightened FoC. High levels of C further influenced FoC, which subsequently had an effect on individuals’ greater punitiveness. The current study supports the previous literature regarding variables that influence FoC and attitudes to punishment, and establishes novel associations involving personality.     

Overt and relational forms of reactive aggression in adolescents: Relations with temperamental reactivity and self-regulation

This study examined whether overt and relational forms of reactive aggression were differentially related to adolescents’ temperament. Measures of adolescents’ temperament and aggression were completed by 670 adolescents (369 females), ages 10–17, and their mothers. Effortful control and fearfulness were inversely associated only with reactive–overt aggression, whereas frustration proneness was more strongly linked with reactive–relational aggression. Furthermore, amongst younger adolescents, effortful control had a larger association with reactive–overt aggression when fearfulness was low, whereas frustration proneness had a stronger relation to reactive–relational aggression when effortful control was high. The differential relations between the two forms of reactive aggression (i.e., overt and relational) and effortful control or fearfulness are discussed with respect to variations in the riskiness and the social competence required to implement these aggressive actions.     

Multimodal assessment of disgust in contamination-related obsessive-compulsive disorder

The present study utilizes multiple methods to examine the relationship between disgust and contamination-related obsessive-compulsive disorder (OCD) symptoms in an analogue sample. Questionnaire findings revealed that participants with high OCD contamination concerns showed stronger disgust sensitivity than did participants with low OCD contamination symptoms after controlling for negative affect. High OCD participants (N=30) also reported significantly more disgust than did low OCD participants (N=30) when exposed to a disgust-inducing video, whereas no significant between-group differences were detected on other negative emotional dimensions. Results from a series of disgust-specific behavioral avoidance tasks (BATs) revealed that high OCD participants demonstrated both less compliance and less approach behavior. Subsequent analysis also revealed that disgust sensitivity generally mediated avoidance on the BATs among high OCD subjects. High OCD participants also rated the BATs as more fearful and disgusting than did low OCD participants, with disgust generally emerging as the dominant emotional response. The results are consistent with a disgust-based, disease-avoidance approach in understanding contamination-related OCD themes.     

Fear conditioning and extinction in anxiety- and depression-prone persons

Anxiety and depression frequently co-occur and may share similar deficits in the processing of emotional stimuli. High anxiety is associated with a failure in the acquisition and extinction of fear conditioning. Despite the supposed common deficits, no research has been conducted on fear acquisition and extinction in depression. The main aim of the present study was to investigate and compare fear acquisition and extinction in anxiety- and depression-prone participants. Non-clinical anxious, depressive, anxious-depressive and control participants performed a fear discrimination task. During acquisition, the CS+ predicted an aversive event (unconditioned stimulus, US) and the CS? safety (no US). During extinction, the CS+ was no longer followed by the US, rendering it (temporarily) into a safety signal. On each CS participants rated their US expectancy; skin conductance responses (SCRs) were measured throughout. The expectancy scores indicated that high anxiety resulted in less safety learning during acquisition and extinction; no effect of depression was observed. SCRs showed that high-anxiety persons displayed less discrimination learning (CS+ minus CS?) during acquisition than low-anxiety persons. During extinction, high-depression persons demonstrated more discriminative SCR than low-depression persons. The observed discrepancies in response patterns of high-anxiety and -depression persons seem to indicate distinctive information processing of emotional stimuli.     

实验性恶心与呕吐——大脑皮层与内脏相关研究的新途径

大脑皮层与内脏关系的脑机制是揭示心身疾病和心理疾病的重要依据。本文综述了经典条件学习与期待性恶心与呕吐的关系以及实验性恶心与呕吐的研究方法。作者认为,实验性恶心与呕吐结合脑成像技术是研究大脑皮层与内脏关系神经机制的重要途径。     

Verbal instructions targeting valence alter negative conditional stimulus evaluations (but do not affect reinstatement rates)

Negative conditional stimulus (CS) valence acquired during fear conditioning may enhance fear relapse and is difficult to remove as it extinguishes slowly and does not respond to the instruction that unconditional stimulus (US) presentations will cease. We examined whether instructions targeting CS valence would be more effective. In Experiment 1, an image of one person (CS+) was paired with an aversive US, while another (CS?) was presented alone. After acquisition, participants were given positive information about the CS+ poser and negative information about the CS? poser. Instructions reversed the pattern of differential CS valence present during acquisition and eliminated differential electrodermal responding. In Experiment 2, we compared positive and negative CS revaluation by providing positive/negative information about the CS+ and neutral information about CS?. After positive revaluation, differential valence was removed and differential electrodermal responding remained intact. After negative revaluation, differential valence was strengthened and differential electrodermal responding was eliminated. Unexpectedly, the instructions did not affect the reinstatement of differential electrodermal responding.     

Subjective,physiological, and behavioural responses towards evaluatively conditioned stimuli

Evaluative Conditioning (EC) is commonly defined as the change in liking of a stimulus (conditioned stimulus, CS) due to its pairings with an affective unconditioned stimulus (US). In Experiment 1, we investigated effects of repeated stimulus pairings on affective responses, i.e. valence and arousal ratings, pupil size, and duration estimation. After repeatedly pairing the CSs with affective USs, a consistent pattern of affective responses emerged: The CS_negative was rated as being more negative and more arousing, resulted in larger pupils, and was temporally overestimated compared to the CS_neutral. In Experiment 2, the influence of a mere instruction about the contingency between a CS and US on affective responses was examined. After mere instruction about upcoming pairings between the CS and US, subjective ratings also changed, but there was neither evidence for differential pupillary responses nor for differential temporal processing. The results indicate that EC via pairings or instructions can change the affective responses towards formerly neutral stimuli and introduce pupil size as a physiological measure in EC research. However, Experiment 2 suggests that there might be moderating factors based on the type of EC procedure involved.     

Personality traits and individual differences predict threat-induced changes in postural control

This study explored whether specific personality traits and individual differences could predict changes in postural control when presented with a height-induced postural threat. Eighty-two healthy young adults completed questionnaires to assess trait anxiety, trait movement reinvestment (conscious motor processing, movement self-consciousness), physical risk-taking, and previous experience with height-related activities. Tests of static (quiet standing) and anticipatory (rise to toes) postural control were completed under low and high postural threat conditions. Personality traits and individual differences significantly predicted height-induced changes in static, but not anticipatory postural control. Individuals less prone to taking physical risks were more likely to lean further away from the platform edge and sway at higher frequencies and smaller amplitudes. Individuals more prone to conscious motor processing were more likely to lean further away from the platform edge and sway at larger amplitudes. Individuals more self-conscious about their movement appearance were more likely to sway at smaller amplitudes. Evidence is also provided that relationships between physical risk-taking and changes in static postural control are mediated through changes in fear of falling and physiological arousal. Results from this study may have indirect implications for balance assessment and treatment; however, further work exploring these factors in patient populations is necessary.