A glass full of optimism: Enrichment effects on cognitive bias in a rat model of depression

Investigations of cognitive biases in animals are conceptually and translationally valuable because they contribute to animal welfare research and help to extend and refine our understanding of human emotional disorders, where biased information processing is a critical causal and maintenance factor. We employed the "learned helplessness" genetic rat model of depression in studying cognitive bias and its modification by environmental manipulations. Using a spatial judgment task, responses to ambiguous spatial cues were assessed before and after environmental enrichment to test whether this manipulation would cause an optimistic shift in emotional state. Twenty-four congenitally helpless and nonhelpless male rats were trained to discriminate two different locations, "rewarded" versus "aversive." After successful acquisition of this spatial discrimination, cognitive bias was probed by measuring responses to three ambiguous locations. Latencies to "reach" and to actively "choose" a goal pot were recorded alongside exploratory behaviors. An overall strain difference was observed, with helpless rats displaying longer "reach" latencies than nonhelpless rats. This implies a "pessimistic" response bias in helpless rats, underscoring their depressive-like phenotype. No strain differences were observed regarding other behavioral measures. Half of the animals were then transferred to enriched cages and retested. Environmental enrichment resulted in reduced "choose" latencies in both rat strains, associating enrichment with more optimistic interpretations of ambiguous cues. Our results emphasize the suitability of cognitive bias measurement for animal emotion assessment. They extend the methodological repertoire for characterizing complex phenotypes and bear implications for animal welfare research and for the use of animal models in preclinical research.     

The testing effect as a function of explicit testing instructions and judgments of learning

During study, people monitor their learning; the output of this monitoring is captured in so-called judgments of learning (JOLs). JOLs predict later recall better if they are made after a slight delay, instead of immediately after study (the delayed JOL effect). According to the self-fulfilling prophecy (SFP) hypothesis delayed JOLs are based on covert retrieval attempts from long-term memory, and successful retrieval attempts in themselves enhance learning (the testing effect). We compared memory for 40 Swahili-Swedish paired associates after a week as a function of three different learning conditions, namely study plus (i) explicitly instructed self-testing, (ii) delayed JOLs, or (iii) less self-testing. We showed that repeated delayed JOLs lead to a memory improvement that does not differ significantly from a comparable condition where the participants are explicitly testing memory, and both the latter groups performed reliably better than a group that self-tested less. The results suggest that delayed JOLs improve long-term retention as efficiently as explicit memory testing and lend support to the SFP hypothesis.     

Listening to music and physiological and psychological functioning: the mediating role of emotion regulation and stress reactivity

Music listening has been suggested to have short-term beneficial effects. The aim of this study was to investigate the association and potential mediating mechanisms between various aspects of habitual music-listening behaviour and physiological and psychological functioning. An internet-based survey was conducted in university students, measuring habitual music-listening behaviour, emotion regulation, stress reactivity, as well as physiological and psychological functioning. A total of 1230 individuals (mean?=?24.89?±?5.34 years, 55.3% women) completed the questionnaire. Quantitative aspects of habitual music-listening behaviour, i.e. average duration of music listening and subjective relevance of music, were not associated with physiological and psychological functioning. In contrast, qualitative aspects, i.e. reasons for listening (especially 'reducing loneliness and aggression', and 'arousing or intensifying specific emotions') were significantly related to physiological and psychological functioning (all p?=?0.001). These direct effects were mediated by distress-augmenting emotion regulation and individual stress reactivity. The habitual music-listening behaviour appears to be a multifaceted behaviour that is further influenced by dispositions that are usually not related to music listening. Consequently, habitual music-listening behaviour is not obviously linked to physiological and psychological functioning.     

The Social Representations of the Bali Climate Conference in the French and German Media

Climate change is a major current affair for which recent United Nations climate conferences aim to build consensus and develop international solutions. The objective of this article is to compare, through the theoretical lens of social representations, the way in which French and German media, specifically newspapers, represent the Bali climate conference. We use the triangulation of data analysis to take both the pragmatic and the semantic aspects of media discourse into account. Results show that German media adopt both a local and a global vision of climate change and of the conference. Religious metaphors highlight a moral dimension of the conference, suggesting anchoring in human and political categories. In contrast, in French media, we identify that conflicts between countries render the stakes of climate change concrete by war metaphors. The French discourses examined are shown to be organised through the anchoring of political and financial categories. Results are discussed in relation to the history of green movements in the two countries and in relation to practical implications. Copyright © 2011 John Wiley & Sons, Ltd.     

Gibbons (Hylobates pileatus, H. moloch, H. lar, Symphalangus syndactylus) follow human gaze, but do not take the visual perspective of others

We investigated four gibbon species of two different genera (Hylobates pileatus, H. moloch, H. lar, Symphalangus syndactylus) in terms of their looking behavior in response to a human who either looked up or looked at the gibbon. Comparing those two conditions, gibbons as a group looked up more when the human was looking up, but they also performed more looks in other directions and thus generally looked more in this condition. Unlike great apes, gibbons did not respond differently between conditions when only the first look on every trial was considered. Furthermore, they did not perform double looks up to check where the human was looking and also did not habituate to the human’s looks up. This suggests that gibbons co-orient with human gaze, but unlike great apes, they do not take the visual perspective of others.     

The effects of delay on neonatal retention of habituated head-turning

Recovery of neonatal head orientation following auditory habituation was used to examine the effects of intertrial delay. One of two words served as stimuli with criterion orienting and habituation established before the delay. Fifty-six full-term neonates were assigned randomly to one of four delay groups: 10 (control), 55, 100, or 145 s. The percentage of head-turns toward the sound source (with one turn per trial) for blocks of three trials served as the principal dependent variable. Recovery of localized head-turning increased as length of delay increased, with the 100- and 145-s groups showing greater recovery than the 10- and 55-s groups. Infants presented with control trials systematically turned away from the sound source following habituation. Selective sensory adaptation, spontaneous recovery, and short-term memory interpretations of these data are considered.     

Do Co-Worker Conflicts Enhance Daily Worries about Job Insecurity: A Diary Study

The long-term negative consequences of job insecurity on employees’ health and well-being have been demonstrated by several studies, but there is very little evidence on the daily experience of job insecurity and on the factors that may influence it. Therefore, we investigated whether short-term changes occur in the experience of job insecurity and whether these are influenced by daily co-worker conflicts. We carried out a diary study, in which 66 employees answered a questionnaire over the course of five working days. We conducted a multilevel analysis in which we included co-worker conflicts as a predictor, and type of contract, emotional stability, and aggregated job insecurity perceptions as control variables. Our results revealed that job insecurity varies on a daily level, and that 23 per cent of the variance could be explained at a within-person level. Co-worker conflicts were a significant positive predictor for perceived job insecurity in subsequent days after controlling for aggregated job insecurity perceptions at person level. Reversed causation was not found. Practical implications for organisations should focus on the promotion of positive social relations in the work environment in order to mitigate or avoid the negative consequences of social stressors in uncertain times.     

Trends in attempted suicide in Denmark, 1976-1980

The object of the present study was to estimate proportions and changes in the incidence of suicide attempts in Denmark. Case sheets concerning all admissions in 1976-1979 (total 6,650) at the Department of Psychiatry, Odense University Hospital (the catchment area of which provides a representative sample of the Danish population), were examined with a view to establishing the reasons for admission. Rates of suicide attempts by age and sex in 1976-1979 were calculated, and estimated rates of the suicide attempts in 1980 added. Trend analysis showed an increase in the mean rates from 1976 to 1979 of 48%, followed by a decrease in 1980 of 13%. There were high increases among the adolescents, but the increase was above all due to the fact that more and more men attempted suicide; the study suggests as a new phenomenon more male than female suicide attempters. We stress the fact that incidences calculated on the basis of hospital admissions only underestimate the real proportions of self-destructive behavior.