Cognitive costs of encoding novel natural activities: Can “learning by doing” be distracting and deceptive?

Findings from action memory research suggest that the enactment of simple actions and naturalistic activities results in similar memory performance to that from their observation. However, little is known about potential differences between the conditions during the encoding of the to-be-studied actions and activities. We analysed the cognitive costs of encoding two novel naturalistic activities studied via enactment or via observation in four experiments. In addition to memory performance, we measured objective cognitive costs with a secondary task and subjective cognitive costs with repeated ratings of mental effort and estimates of general activity difficulty. Memory performance was comparable across study conditions throughout all experiments. The enactment of activities repeatedly resulted in slower reaction times in the secondary task than did observation, suggesting higher objective costs. In contrast, subjective costs were rated lower after enactment than after observation. Findings from a pantomimic enactment condition suggested that the low ratings of subjective costs after enactment represent a misinterpretation of task demands. Our findings imply that the widespread belief about “learning by doing” as an easy way of learning does not stem from an actual advantage in memory performance, but rather from continuous feedback about one's performance resulting from enactment.     

Choose your lunch companion wisely: the relationships between lunch break companionship,psychological detachment,and daily vigour

This diary study examines psychological detachment, companionship, and content of conversation during lunch break as predictors of daily vigour after lunch break and at the end of the working day. Drawing on resource regulation theory and the effort recovery model (ERM), we hypothesize that companionship of the supervisor during lunch break is negatively and companionship of colleagues positively related to employee’s daily vigour. The companionship of both, supervisors and colleagues, as well as work-related conversations are hypothesized to decrease psychological detachment during lunch breaks. In total, 71 persons in administrative jobs completed daily surveys over one working week. Results of hierarchical linear modelling showed that psychological detachment is positively related to vigour after lunch break, but unrelated to vigour at the end of the working day. Lunch breaks with the supervisor predicted a lower level of vigour at the end of the working day, but a higher level of vigour after lunch break. Lunch breaks with colleagues were unrelated to vigour after lunch break, but associated with higher vigour at the end of a working day. The companionship of both—colleagues and supervisors—as well as work-related conversation decreased psychological detachment during lunch break.     

Socioeconomic and sociocultural determinants of psychological distress and quality of life among patients with psoriasis in a selected multi-ethnic Malaysian population

Patients with psoriasis may have increased risk of psychological comorbidities. This cross-sectional study aimed at determining associations between sociocultural and socioeconomic factors with the Depression Anxiety Stress Scale (DASS) scores and the Dermatology Life Quality Index (DLQI) scores. Adult patients with psoriasis were recruited from a Dermatology outpatient clinic via convenience sampling. Interviews were conducted regarding socio-demographic factors and willing subjects were requested to complete the DASS and DLQI questionnaires. The Pearson χ² test, Fisher’s exact test and multivariate logistic regression were used for statistical analysis to determine independent predictors of depression, anxiety, stress and severe impairment of quality of life. Unadjusted analysis revealed that depression was associated with Indian ethnicity (p = .041) and severe impairment of quality of life was associated with Indian ethnicity (p = .032), higher education (p = .013), higher income (p = .042), and employment status (p = .014). Multivariate analysis revealed that Indian ethnicity was a predictor of depression (p = .024). For stress, tertiary level of education (p = .020) was an independent risk factor while a higher monthly income was a protective factor (p = .042). The ethnic Indians and Malays were significantly more likely than the ethnic Chinese to suffer reduced quality of life (p = .001 and p = .006 respectively) and subjects with tertiary education were more likely to have severe impairment of quality of life (p = .002). Our study was unique in determining sociocultural influences on psychological complications of psoriasis in a South East Asian population. This has provided invaluable insight into factors predictive of adverse effects of psoriasis on psychological distress and quality of life in our patient population. Future studies should devise interventions to specifically target at risk groups in the development of strategies to reduce morbidity associated with psoriasis.     

Meerkats (<Emphasis Type="Italic">Suricata suricatta</Emphasis>) fail to prosocially donate food in an experimental set-up

Although humans are usually believed to be prosocial, the evolutionary origins of prosociality are largely debated. One hypothesis is that cooperative breeding has been one major precursor to the emergence of prosociality. In vertebrates, however, experimental evidence of prosociality has been mainly gathered in non-human primates. In this study, we tested the cooperative breeding hypothesis in cooperative breeding meerkats (Suricata suricatta). In particular, we tested whether meerkats take into account partners’ benefits when distributing food rewards. Nine individuals were presented with two platforms baited with different food distributions (providing food to themselves, to a partner or both). In all conditions, the decision to operate the apparatus was based on the presence of food on the subject’s side, and not on the possible benefits to partners. Despite being cooperative breeders, meerkats in this study failed to be prosocial, suggesting that prosociality in this species may be limited to specific contexts.     

Are parrots poor at motor self-regulation or is the cylinder task poor at measuring it?

The ability to inhibit unproductive motor responses triggered by salient stimuli is a fundamental inhibitory skill. Such motor self-regulation is thought to underlie more complex cognitive mechanisms, like self-control. Recently, a large-scale study, comparing 36 species, found that absolute brain size best predicted competence in motor inhibition, with great apes as the best performers. This was challenged when three Corvus species (corvids) were found to parallel great apes despite having much smaller absolute brain sizes. However, new analyses suggest that it is the number of pallial neurons, and not absolute brain size per se, that correlates with levels of motor inhibition. Both studies used the cylinder task, a detour-reaching test where food is presented behind a transparent barrier. We tested four species from the order Psittaciformes (parrots) on this task. Like corvids, many parrots have relatively large brains, high numbers of pallial neurons, and solve challenging cognitive tasks. Nonetheless, parrots performed markedly worse than the Corvus species in the cylinder task and exhibited strong learning effects in performance and response times. Our results suggest either that parrots are poor at controlling their motor impulses, and hence that pallial neuronal numbers do not always correlate with such skills, or that the widely used cylinder task may not be a good measure of motor inhibition.