Shedding light on photosensitive behaviour in brown planaria (Dugesia Tigrina)

The planarian flatworm is one of the simplest animals to develop two eyecups that enable them to detect the presence and direction of light, which they typically avoid. In this study we assessed responses of planaria to different intensities of light. We found that they exhibited a graded, sigmoidal, photonegative response to light intensity. A two-octave increase in luminance (on the upward slope of the sigmoid) corresponded to a 9% increase in the speed planaria travelled to avoid light.     

Maternal defense: breast feeding increases aggression by reducing stress

Mothers in numerous species exhibit heightened aggression in defense of their young. This shift typically coincides with the duration of lactation in nonhuman mammals, which suggests that human mothers may display similarly accentuated aggressiveness while breast feeding. Here we report the first behavioral evidence for heightened aggression in lactating humans. Breast-feeding mothers inflicted louder and longer punitive sound bursts on unduly aggressive confederates than did formula-feeding mothers or women who had never been pregnant. Maternal aggression in other mammals is thought to be facilitated by the buffering effect of lactation on stress responses. Consistent with the animal literature, our results showed that while lactating women were aggressing, they exhibited lower systolic blood pressure than did formula-feeding or never-pregnant women while they were aggressing. Mediation analyses indicated that reduced arousal during lactation may disinhibit female aggression. Together, our results highlight the contributions of breast feeding to both protecting infants and buffering maternal stress.     

Just for Fun: The Playful Image of Nanotechnology

In 1959, Richard Feynman suggested that the most compelling reason to pursue nanoscale research might be ‘just for fun.’ This article traces a history of playful images and ludic practices in nanotechnology. Two case studies—nanocars and nanosoccer—exemplify the ways in which scientific research mobilizes speculative futures, less through engineering design or stepwise protocol than through the recreational dynamics of play. Although such molecular toys might appear frivolous, they index the increasingly widespread conditions of play labor, or ‘playbor’, shaping today’s technoculture. Exploring the processes of transmutation and transvaluation by which technological imaginaries are rendered operative, this article tells a story of how the nanoworld became an everyday reality by becoming a game.     

A retrospective analysis of the relation between resurgence and renewal of behavior targeted for reduction

Functional communication training (FCT) is an evidence-based treatment for behavior targeted for reduction that often combines extinction for target responses and arranges functionally equivalent reinforcement for alternative behavior. Long-term effectiveness of FCT can become compromised when transitioning from clinic to nonclinic contexts or thinning reinforcement schedules for appropriate behavior. Such increases in targeted behavior have been conceptualized as renewal and resurgence, respectively. The relation between resurgence and renewal has yet to be reported. Therefore, the present report retrospectively analyzed the relation between renewal and resurgence in data collected when implementing FCT with children diagnosed with developmental disabilities. We found no relation when evaluating all 34 individuals assessed for resurgence and renewal or a subset of individuals exhibiting both resurgence and renewal. These findings suggest that one form of relapse may not be predictive of another form of relapse.     

Bayesian just-so stories in psychology and neuroscience

According to Bayesian theories in psychology and neuroscience, minds and brains are (near) optimal in solving a wide range of tasks. We challenge this view and argue that more traditional, non-Bayesian approaches are more promising. We make 3 main arguments. First, we show that the empirical evidence for Bayesian theories in psychology is weak. This weakness relates to the many arbitrary ways that priors, likelihoods, and utility functions can be altered in order to account for the data that are obtained, making the models unfalsifiable. It further relates to the fact that Bayesian theories are rarely better at predicting data compared with alternative (and simpler) non-Bayesian theories. Second, we show that the empirical evidence for Bayesian theories in neuroscience is weaker still. There are impressive mathematical analyses showing how populations of neurons could compute in a Bayesian manner but little or no evidence that they do. Third, we challenge the general scientific approach that characterizes Bayesian theorizing in cognitive science. A common premise is that theories in psychology should largely be constrained by a rational analysis of what the mind ought to do. We question this claim and argue that many of the important constraints come from biological, evolutionary, and processing (algorithmic) considerations that have no adaptive relevance to the problem per se. In our view, these factors have contributed to the development of many Bayesian "just so" stories in psychology and neuroscience; that is, mathematical analyses of cognition that can be used to explain almost any behavior as optimal.     

Widening the boundaries of the production effect

Words that are read aloud are more memorable than words that are read silently. The boundaries of this production effect (MacLeod, Gopie, Hourihan, Neary, & Ozubko, Journal of Experimental Psychology: Learning, Memory, and Cognition, 36, 671-685, 2010) have been found to extend beyond speech. MacLeod and colleagues demonstrated that mouthing also facilitates memory, leading them to speculate that any distinct, item-specific response should result in a production effect. In Experiment 1, we found support for this conjecture: Relative to silent reading, three unique productions-spelling, writing, and typing-all boosted explicit memory. In Experiment 2, we tested the sensitivity of the production effect. Although mouthing, writing, and whispering all improved explicit memory when compared to silent reading, these other production modalities were not as beneficial as speech. We argue that the enhanced distinctiveness of speech relative to other productions-and of other productions relative to silent reading-underlies this pattern of results.     

Production benefits learning: The production effect endures and improves memory for text

The production effect is the superior retention of material read aloud relative to material read silently during an encoding episode. Thus far it has been explored using isolated words tested almost immediately. The goal of this study was to assess the efficacy of production as a study strategy, addressing: (a) whether the production benefit endures beyond a short session, (b) whether production can boost memory for more complex material, and (c) whether production transfers to educationally relevant tests. In Experiment 1 a 1-week retention interval was included, and a production effect was observed. In Experiment 2 a production effect was observed for both word pairs and sentence stimuli. In Experiment 3 educationally relevant essays were read and tested with a fill-in-the-blanks test: Memory was superior for questions that probed information that had been read aloud relative to information that had been read silently. We conclude that the production benefit is enduring and generalises to text and different test formats, indicating that production constitutes a worthwhile study strategy.     

Counselling in the workplace: How time‐limited counselling can effect change in well‐being

Background: Many employers provide counselling support on work and personal issues for their employees, but in times of economic pressure such services can be at risk if their effectiveness is not demonstrated. Aim: To evaluate whether time‐limited counselling in a workplace can effect sustained change in well‐being. Method: The study was carried out by a staff counselling team in a university setting. The Warwick‐Edinburgh Mental Well‐being Scale (WEMWBS) was completed by clients at the beginning and end of counselling, and at three and six months following. A non‐treatment comparison group completed the survey at the same intervals. Results: The results of our investigation show clearly that the effect of time‐limited counselling (average seven sessions) on distressed clients is positive. The evidence of our treatment group suggests that they acquire an increased sense of well‐being as a result of the experience of counselling with a significant statistical difference between pre‐and post‐counselling treatment group scores on the WEMWBS and consistently higher scores found post counselling. The improvement was maintained at the same level for at least six months following the end of counselling. Conclusions: The provision of time‐limited counselling by employers is an effective support for personal difficulties affecting work.