Savant-like numerosity skills revealed in normal people by magnetic pulses

Oliver Sacks observed autistic twins who instantly guessed the exact number of matchsticks that had just fallen on the floor, saying in unison "111". To test the suggestion that normal individuals have the capacity for savant numerosity, we temporarily simulated the savant condition in normal people by inhibiting the left anterior temporal lobe of twelve participants with repetitive transcranial magnetic stimulation (rTMS). This site has been implicated in the savant condition. Ten participants improved their ability to accurately guess the number of discrete items immediately following rTMS and, of these, eight became worse at guessing as the effects of the pulses receded. The probability of as many as eight out of twelve people doing best just after rTMS and not after sham stimulation by chance alone is less than one in one thousand.     

The role of fear-relevant stimuli in visual search: a comparison of phylogenetic and ontogenetic stimuli

It has been argued that phylogenetic fear-relevant stimuli elicit preattentive capture of attention. To distinguish between fear relevance and time of appearance in evolutionary history, the authors compare phylogenetic and ontogenetic fear-relevant and fear-irrelevant stimuli in a visual search task. The authors found no evidence for a special role of phylogenetic fear-relevant stimuli; it seems that fear relevance in general is more important than is the evolutionary age. The pattern of results indicates that attention toward threatening stimuli is mainly affected by a late component that prolongs the disengagement of attention.     

Computational and behavioral markers of model-based decision making in childhood

Human decision-making is underpinned by distinct systems that differ in flexibility and associated cognitive cost. A widely accepted dichotomy distinguishes between a cheap but rigid model-free system and a flexible but costly model-based system. Typically, humans use a hybrid of both types of decision-making depending on environmental demands. However, children's use of a model-based system during decision-making has not yet been shown. While prior developmental work has identified simple building blocks of model-based reasoning in young children (1–4 years old), there has been little evidence of this complex cognitive system influencing behavior before adolescence. Here, by using a modified task to make engagement in cognitively costly strategies more rewarding, we show that children aged 5–11-years (N = 85), including the youngest children, displayed multiple indicators of model-based decision making, and that the degree of its use increased throughout childhood. Unlike adults (N = 24), however, children did not display adaptive arbitration between model-free and model-based decision-making. Our results demonstrate that throughout childhood, children can engage in highly sophisticated and costly decision-making strategies. However, the flexible arbitration between decision-making strategies might be a critically late-developing component in human development.     

Global news – global identity? The relationship between media consumption,perception of identity,and ethnocentrism

In line with the common ingroup identity model, the present research investigated whether factors beyond contact conditions are associated with the emergence of a shared identity perception and outgroup attitudes. Concretely, we reasoned that higher consumption of global news would be positively related to a stronger global identity, which in turn would be negatively correlated with ethnocentrism. In contrast, consumption of local news should be associated with a local identity, which would then be positively related to ethnocentrism. To test these ideas, one cross-sectional (N = 576) and one longitudinal study (N = 410) were carried out at an Austrian university. As hypothesized, global news consumption was associated with a stronger global identity, which then accounted for reduced ethnocentrism. However, only in the cross-sectional study, we found empirical evidence that local news interest is positively correlated with ethnocentrism mediated by local identity.     

Spillover and crossover effects of exposure to work-related aggression and adversities: A dyadic diary study

The past two decades have produced extensive evidence on the manifold and severe outcomes for victims of aggression exposure in the workplace. However, due to the dominating individual-centered approach, most findings miss a social network perspective. Consequently, knowledge of negative spillover to different life-domains or crossover to uninvolved individuals alongside a detailed understanding of the involved transmission processes remains scarce. By integrating social aggression theorizing, the present study investigated transmission routes (emphatic, behavioral) of experienced adversities and aggression at work toward perpetration of aggressive behavior and potential spillover and crossover effects into the private life domain in a diary study of 72 mixed dyads. Analyses of mediation based upon the Actor-Partner Interdependence Model revealed an association between the frequency of perpetrating aggressive behavior in the work context and a spillover into the private life domain via aggression-promoting internal states (emotions, cognitions, arousal). Based on the different patterns of mediation, it appears that adversities follow a mental transmission process, whereby experienced aggression displayed behavioral assimilation. In contrast, no crossover effects of exposure to adversities or aggression at work to a study partner at home could be detected. Practical and theoretical implications as well as limitations and ideas for future work are discussed.     

Drosophila Mushroom Bodies Are Dispensable for Visual, Tactile, and Motor Learning

A total of 18 associative learning/memory tests have been applied to Drosophila melanogaster flies lacking mushroom bodies. Only in paradigms involving chemosensory cues as conditioned stimuli have flies been found to be compromised by a block in the mushroom body pathway. Among the learning tasks not requiring these structures are a case of motor learning (yaw torque/heat), a test of the fly’s spatial orientation in total darkness, conditioned courtship suppression by mated females, and nine different examples of visual learning. The latter used the reinforcers of heat, visual oscillations, mechanical shaking, or sucrose, and as conditioned stimuli, color, intensity contrast, as well as stationary and moving visual patterns. No forms of consolidated memory have been tested in mushroom body-less flies. With respect to short-term memory the mushroom bodies of Drosophila are specially required for chemosensory learning tasks, but not for associative learning and memory in general.     

Recipient Design in Communicative Pointing

A long‐standing debate in the study of human communication centers on the degree to which communicators tune their communicative signals (e.g., speech, gestures) for specific addressees, as opposed to taking a neutral or egocentric perspective. This tuning, called recipient design, is known to occur under special conditions (e.g., when errors in communication need to be corrected), but several researchers have argued that it is not an intrinsic feature of human communication, because that would be computationally too demanding. In this study, we contribute to this debate by studying a simple communicative behavior, communicative pointing, under conditions of successful (error‐free) communication. Using an information‐theoretic measure, called legibility, we present evidence of recipient design in communicative pointing. The legibility effect is present early in the movement, suggesting that it is an intrinsic part of the communicative plan. Moreover, it is reliable only from the viewpoint of the addressee, suggesting that the motor plan is tuned to the addressee. These findings suggest that recipient design is an intrinsic feature of human communication.     

A Predictive Approach to Nonparametric Inference for Adaptive Sequential Sampling of Psychophysical Experiments

We present a predictive account on adaptive sequential sampling of stimulus-response relations in psychophysical experiments. Our discussion applies to experimental situations with ordinal stimuli when there is only weak structural knowledge available such that parametric modeling is no option. By introducing a certain form of partial exchangeability, we successively develop a hierarchical Bayesian model based on a mixture of Pólya urn processes. Suitable utility measures permit us to optimize the overall experimental sampling process. We provide several measures that are either based on simple count statistics or more elaborate information theoretic quantities. The actual computation of information theoretic utilities often turns out to be infeasible. This is not the case with our sampling method, which relies on an efficient algorithm to compute exact solutions of our posterior predictions and utility measures. Finally, we demonstrate the advantages of our framework on a hypothetical sampling problem.