Adolescents let sufficient evidence accumulate before making a decision when large incentives are at stake

Adolescent decision‐making has been described as impulsive and suboptimal in the presence of incentives. In this study we examined the neural substrates of adolescent decision‐making using a perceptual discrimination task for which small and large rewards were associated with correctly detecting the direction of motion of a cloud of moving dots. Adults showed a reward bias of faster reaction times on trials for which the direction of motion was associated with a large reward. Adolescents, in contrast, were slower to make decisions on trials associated with large rewards. This behavioral pattern in adolescents was paralleled by greater recruitment of fronto‐parietal regions important in representing the accumulation of evidence sufficient for selecting one choice over its alternative and the certainty of that choice. The findings suggest that when large incentives are dependent on performance, adolescents may require more evidence to accumulate prior to responding, to be certain to maximize their gains. Adults, in contrast, appear to be quicker in evaluating the evidence for a decision when primed by rewards. Overall these findings suggest that rather than reacting hastily, adolescents can be incentivized to take more time to make decisions when large rewards are at stake. A video abstract of this article can be viewed at http://youtu.be/1g4F5vzFDl0     

A longitudinal investigation of children internationally adopted at school age

Most existing research on children adopted internationally has focused on those adopted as infants and toddlers. The current study longitudinally tracked several outcomes, including cognitive, behavioral, emotional, attachment, and family functioning, in 25 children who had been internationally adopted at school age (M = 7.7 years old at adoption, SD = 3.4, range = 4–15 years). We examined the incidence of clinically significant impairments, significant change in outcomes over the three study points, and variables that predicted outcomes over time. Clinically significant impairments in sustained attention, full-scale intelligence, reading, language, executive functioning, externalizing problems, and parenting stress were common, with language and executive functioning impairments present at higher levels in the current study compared with past research focusing on children adopted as infants and toddlers. Over the three study points, significant improvements across most cognitive areas and attachment functioning were observed, though significant worsening in executive functioning and internalizing problems was present. Adoptive family-specific variables, such as greater maternal education, smaller family size, a parenting approach that encouraged age-expected behaviors, home schooling, and being the sole adopted child in the family were associated with greater improvement across several cognitive outcomes. In contrast, decreased parenting stress was predicted by having multiple adopted children and smaller family sizes were associated with greater difficulties with executive functioning. Child-specific variables were also linked to outcomes, with girls displaying worse attachment and poorer cognitive performance and with less time in orphanage care resulting in greater adoption success. Implications for future research and clinical applications are discussed.     

‘Animals run about the world in all sorts of paths’: varieties of indeterminism

Synthese - In her seminal essay ‘Causality and Determination’, Elizabeth Anscombe very decidedly announced that “physical indeterminism” is “indispensable if we are to...     

Action as a Window to Perception: Measuring Attention with Mouse Movements

Eye‐gaze tracking has been shown to deliver valuable information about how people view advertisements and what they pay attention to. However, practical difficulties in its application limit its usability by marketing researchers. Here, we explore the use of mouse tracking to evaluate viewing behavior by determining whether the hand can be trained to follow visual spatial attention and whether visual processing can be estimated by tracking pointing movements made with a computer mouse. In brief, the results of the research are very promising, showing high correlations between the scan paths for the eye and the mouse, as well as high correlations between the percentage of time spent in designated regions of interest for the mouse and the eye. An additional comparison of the data with that of a group who did not use a mouse while viewing the experimental stimuli showed that viewing patterns were not disrupted by mouse use. Copyright © 2012 John Wiley & Sons, Ltd.     

Making snacking less sinful: (Counter-)moralising obesity in the public discourse differentially affects food choices of individuals with high and low perceived body mass

Objective: As public discourse surrounding obesity highlights the societal costs of obesity and individual’s own responsibility for their weight, being overweight is often framed as immoral. Such ‘moralizing’ messages about being overweight may be a psychological threat for those with high body mass. Attempting to counter-moralise the public discourse (i.e. actively arguing that there is nothing ‘immoral’ about being overweight) may relieve this threat, inducing people, especially those with higher (perceived) weight, to engage in healthier behaviours.

Method: Two experiments were performed among Dutch and US participants. (Counter-)moralisation was manipulated. Body mass and weight-related self-perceptions were measured. The dependent variable was healthy vs. unhealthy snack choice.

Results: (Counter-)moralisation and (perceived) overweight jointly predicted snack choice: counter-moralising messages induced healthy snacking, but only among those who regarded themselves to have a high body mass.

Conclusions: The effects of moralising vs. counter-moralising obesity depended on one’s (perceived) overweight. This suggests that, for people with relatively high weight, the current moralising public discourse on obesity works in counterproductive ways. Campaigns that ‘counter-moralize’ obesity (i.e. that refute moralising messages) are more productive, although they should be tailored to those who see themselves as being overweight.     

Are Older Adults More Dependent on Visual Information in Regulating Self-Motion Than Younger Adults?

Older adults look at the ground more while they are walking than younger adults do. In the present study, the effect of blocking that exproprioceptive visual information on the walking pattern of older adults was investigated. The first 0.75 m of the floor in front of healthy young adults (n = 10, mean age = 26.0 years) and 2 groups of older adults (n = 10, mean age 65.7 years; and n = 9, mean age = 75.9 years) was occluded. The dependent variables were step velocity, step length, and step frequency. The effect of the manipulation on those kinematic variables increased with age. The older adults had a significant increase in velocity and step length. The possible use of optic flow information from the ground to regulate the velocity of self-motion is discussed.     

Sensory Feedback in the Learning of a Novel Motor Task

The role of different forms of feedback is examined in learning a novel motor task. Five groups of ten subjects had to learn the voluntary control of the abduction of the big toe, each under a different feedback condition (proprioceptive feedback, visual feedback, EMG feedback, tactile feedback, force feedback). The task was selected for two reasons. First, in most motor learning studies subjects have to perform simple movements which present hardly any learning problem. Second, studying the learning of a new movement can provide useful information for neuromuscular reeducation, where patients often also have to learn movements for which no control strategy exists. The results show that artificial sensory feedback (EMG feedback, force feedback) is more powerful than “natural” (proprioceptive, visual, and tactile) feedback. The implications of these results for neuromuscular reeducation are discussed.     

Inattentive behaviour is associated with poor working memory and slow processing speed in very pre‐term children in middle childhood

Background. Problem behaviour is common following pre‐term birth, but the underlying nature of these difficulties is not well known. Aims. We sought to establish the mechanisms underpinning behavioural difficulties in very pre‐term (VPT) children in middle childhood by comparing their performance to that of term born peers on tasks of working memory, inhibition, and processing speed, and relating these to parent and teacher assessments of their behaviour. Particular focus was given to inattention and overactive/impulsive behaviour, as these behaviours have been associated with different neuropsychological problems in term children. Samples. A group of VPT children (gestational age < 31 weeks, N= 56) aged 9–10 years and term controls (N= 22) participated in the study. Method. Children were assessed with measures of working memory, inhibition, and processing speed. Parents and teachers reported behavioural problems using the Strengths and Difficulties Questionnaire and two additional scales measuring overactive/impulsive behaviour and inattention. Results. Results revealed increased rates of problem behaviour in VPT compared to term children for parent‐rated total difficulties, hyperactivity, emotional problems, peer problems, prosocial behaviour, overactive/impulsive behaviour, and parent‐ and teacher‐rated inattention. Processing speed and working memory, but not inhibition, were significantly related to inattentive and overactive/impulsive behaviour. Conclusions. The increased rates of inattention and overactive/impulsive behaviour in VPT children may be explained by impairment in processing speed and working memory. Expected links between overactive/impulsive behaviour and inhibitory control were not identified, suggesting the nature of such difficulties may be different in VPT compared to term children.     

Undermining trust and cooperation: The paradox of sanctioning systems in social dilemmas

Sanctioning systems in social dilemmas are often meant to increase trust in others and to increase cooperation. We argue, however, that sanctioning systems may also give people the idea that others act in their own self-interest and undermine the belief that others are internally motivated to cooperate. We developed the “Removing The Sanction” paradigm and a new trust manipulation, and showed in three experiments that when there is a sanction on defection, trust in others being internally motivated to cooperate is undermined: Participants who had experienced the presence of a sanctioning system trusted fellow group members less than participants who had not. In a similar vein, the sanction undermined cooperation when trust was initially high. The implications of these paradoxical findings are discussed.     

Born to adapt, but not in your dreams

The brain adapts to changes that take place in the body. Deprivation of input results in size reduction of cortical representations, whereas an increase in input results in an increase of representational space. Amputation forms one of the most dramatic disturbances of the integrity of the body. The brain adapts in many ways to this breakdown of the afferent–efferent equilibrium. However, almost all studies focus on the sensorimotor consequences. It is not known whether adaptation takes place also at other “levels” in the system. The present study addresses the question whether amputees dream about their intact body, as before the amputation, or about the body after the amputation and whether the dream content was a function of time since the amputation and type of amputation. The results show that the majority of the dreamers reported dreams about their intact body although the mean time that elapsed since the amputation was twelve years. There is no clear relation with the type of amputation. The results give modest evidence for the existence of a basic neural representation of the body that is, at least, partly genetically determined and by this relatively insensitive for changes in the sensory input.