Differential involvement of the central amygdala in appetitive versus aversive learning

Understanding the function of the distinct amygdaloid nuclei in learning comprises a major challenge. In the two studies described herein, we used c-Fos immunolabeling to compare the engagement of various nuclei of the amygdala in appetitive and aversive instrumental training procedures. In the first experiment, rats that had already acquired a bar-pressing response to a partial food reinforcement were further trained to learn that an acoustic stimulus signaled either continuous food reinforcement (appetitive training) or a footshock (aversive training). The first training session of the presentation of the acoustic stimulus resulted in significant increases of c-Fos immunolabeling throughout the amygdala; however, the pattern of activation of the nuclei of the amygdala differed according to the valence of motivation. The medial part of the central amygdala (CE) responded, surprisingly, to the appetitive conditioning selectively. The second experiment was designed to extend the aversive versus appetitive conditioning to mice, trained either for place preference or place avoidance in an automated learning system (INTELLICAGE). Again, much more intense c-Fos expression was observed in the medial part of the CE after the appetitive training as compared to the aversive training. These data, obtained in two species and by means of novel experimental approaches balancing appetitive versus aversive conditioning, support the hypothesis that the central nucleus of the amygdala is particularly involved in appetitively motivated learning processes.     

A preliminary psychometric evaluation of the Hospital Anxiety and Depression Scale (HADS) in 963 people living with a spinal cord injury

This study aimed to evaluate the preliminary psychometric properties of the Hospital Anxiety and Depression Scale (HADS) in a community sample of adults living with a spinal cord injury (SCI). A cross-sectional design was used with 963 people living in the community with an SCI. Participants were recruited via three spinal centres in the United Kingdom. They completed the HADS and the Life Satisfaction Questionnaire. Psychometric analyses were conducted for the whole sample, by gender and level of injury. The HADS demonstrated good internal consistency, with promising content validity. Two factors, approximating to anxiety and depression were extracted via factor analysis for the whole sample, by gender and level of injury. In line with existing literature, females scored significantly higher than males on the anxiety subscale. Item 7 ("I can sit at ease and feel relaxed") was found to be a complex item, with a potentially different meaning within this population. This study presents preliminary findings, which support the psychometric integrity of the HADS within an outpatient population with SCI. Items that included potential somatic components revealed a more complex factor loading profile. Recommendations are made to further investigate this measure with amendments to such items, incorporating inpatients and independent measures of anxiety and depression to address validity directly.     

A cognitive and an affective dimension of alexithymia in six languages and seven populations

The Dutch Bermond–Vorst Alexithymia Questionnaire (BVAQ) is translated into various languages. The aim of this research was to establish the factor structure of subscales on seven cultural groups. The BVAQ consists of five subscales of eight items each: Emotionalising, Fantasising, Analysing, Identifying, and Verbalising emotions. The BVAQ was administered to a group of Dutch students (n=375), a group of English students (n=175), a group of Australian students, university employees and visitors (n=216), a group of French speaking Belgian students (n=175), a group of Italian people (n=791; a mix of various clinical groups), a group of Polish people (n=427; also a mix of various clinical groups) and a group of Russian people (n=141; general population). The hypothesised two-factor structure of an affective alexithymia dimension (Emotionalising, Fantasising) and a cognitive alexithymia dimension (Insight and Verbalising), with “Analysing emotions” loading on both factors, was clearly supported by confirmatory factor analyses (CFA). Both orthogonal and oblique principal components analyses (PCA), without restriction concerning the number of factors, provided the same two-factor solution in all groups explaining between 55% and 64% of the variance. Oblique rotation further demonstrated that the correlations between these two factors were low in all populations. The combined CFA and PCA results, therefore, indicated that a model with two independent factors has to be preferred over the model assuming two correlated factors.     

Is God His Essence? The Logical Structure of Aquinas’ Proofs for this Claim

In this article I consider whether Aquinas’ arguments for the claim that God is His essence are conclusive, and what was his purpose of upholding this thesis. I show his proofs from Summa Theologiae and Summa Contra Gentiles to be problematic and argue that the defense of Aquinas’ views on that matter suggested by certain remarks of P. T. Geach is flawed.     

The chameleon effect,the temporal aspects of mimicry and their impact on service measurement

BackgroundIn an experiment conducted in a natural setting, we test the link between mimicry, the amount of time during which the mimicry behavior takes place, and its impact on service quality.MethodsCable TV clients (n = 120) were randomly assigned to six experimental conditions (2 mimicry conditions: verbal mimicry vs. no mimicry x 3 interaction time: 5 vs. 10 vs. 15 minutes). Perceived service quality served as the dependent measurement.ResultsA main effect of mimicry was found on service quality: a cable TV representative was perceived more favorably when he mimicked the customer. Importantly, it was shown that even small portions of mimicry are beneficial, meaning that practitioners do not have to mimic someone for a long time to achieve benefits.ConclusionThe paper shows new benefits for the mimicker: more positive judgments by the mimickee regarding the impact on several different levels of service quality.     

On individuals in branching histories

Against the background of the theory of branching space-times (BST), the paper sketches a concept of individuals. It discusses Kripkean modal intuitions concerning individuation, and, finally it addresses Lewis??s objections to branching individuals.     

Causation Without Influence

David Lewis’s latest theory of causation defines the causal link in terms of the relation of influence between events. It turns out, however, that one event’s influencing another is neither a necessary nor sufficient condition for its being a cause of that event. In the article one particular case of causality without influence is presented and developed. This case not only serves as a counterexample to Lewis’s influence theory, but also threatens earlier counterfactual analyses of causation by admitting a particularly troublesome type of preemption. The conclusion of the article is that Lewis’s influence method of solving the preemption problem fails, and that we need a new and fresh approach to the cases of redundant causation if we want to hold on to the counterfactual analysis of causation.     

Context-dependent impairment of recollection in list-method directed forgetting

In list-method directed forgetting, people's ability to forget one of the sets of learned material is examined. Research shows that memory for to-be-forgotten items is impaired when assessed by a recall test and by recognition tests reliant on recollective processes. Retrieval inhibition and context-change mechanisms have been proposed to account for the directed forgetting effects and both of them account for the results obtained with recognition tests. However, the context change account makes a specific prediction that recollection is impaired by directed forgetting only if it makes use of contextual associations. In the present study, directed forgetting was examined with two types of recollection-based tasks making use of different types of associations, namely a list discrimination task utilising contextual associations and an associative recognition task utilising interitem associations. Consistent with the context change account, the costs of directed forgetting were observed in a list discrimination task and were not observed in an associative recognition task. The results indicate that impairment in recollection due to directed forgetting is not general and provide converging evidence to support the context-change account.