Walter the banker: the conjunction fallacy reconsidered

In a famous experiment by Tversky and Kahneman (Psychol Rev 90:293–315, 1983), featuring Linda the bank teller, the participants assign a higher probability to a conjunction of propositions than to one of the conjuncts, thereby seemingly committing a probabilistic fallacy. In this paper, we discuss a slightly different example featuring someone named Walter, who also happens to work at a bank, and argue that, in this example, it is rational to assign a higher probability to the conjunction of suitably chosen propositions than to one of the conjuncts. By pointing out the similarities between Tversky and Kahneman’s experiment and our example, we argue that the participants in the experiment may assign probabilities to the propositions in question in such a way that it is also rational for them to give the conjunction a higher probability than one of the conjuncts.     

Microstructural organization of corpus callosum projections to prefrontal cortex predicts bimanual motor learning

The corpus callosum (CC) is the largest white matter tract in the brain. It enables interhemispheric communication, particularly with respect to bimanual coordination. Here, we use diffusion tensor imaging (DTI) in healthy humans to determine the extent to which structural organization of subregions within the CC would predict how well subjects learn a novel bimanual task. A single DTI scan was taken prior to training. Participants then practiced a bimanual visuomotor task over the course of 2 wk, consisting of multiple coordination patterns. Findings revealed that the predictive power of fractional anisotropy (FA) was a function of CC subregion and practice. That is, FA of the anterior CC, which projects to the prefrontal cortex, predicted bimanual learning rather than the middle CC regions, which connect primary motor cortex. This correlation was specific in that FA correlated significantly with performance of the most difficult frequency ratios tested and not the innately preferred, isochronous frequency ratio. Moreover, the effect was only evident after training and not at initiation of practice. This is the first DTI study in healthy adults which demonstrates that white matter organization of the interhemispheric connections between the prefrontal structures is strongly correlated with motor learning capability.     

Physical self-concept and disturbed eating attitudes and behaviors in French athlete and non-athlete adolescent girls: direct and indirect relations

This study aims to investigate the direct and indirect associations between physical self-subdomains, physical self-worth, global self-worth, and disturbed eating attitudes and behaviors among French non-elite athlete and non-athlete adolescent girls. A sample of adolescent girls including 50 ballet dancers, 41 basketball players, and 47 non-athletes was used in this study. Data obtained from the ballet dancer and basketball player subsamples revealed significant, sample-specific as well as common, direct relations between global and physical self-perceptions and disturbed eating attitudes and behaviors, as well as significant indirect relations (via global self-worth and physical self-worth) between specific physical self-perceptions and disturbed eating attitudes and behaviors. In contrast, no association was found between global and physical self-perceptions in the sample of non-athlete adolescent girls.     

Salience from multiple feature contrast: Evidence from saccade trajectories

We used eye tracking to quantify the extent to which combinations of salient contrasts (orientation, luminance, and movement) influence a central salience map that guides eye movements. We found that luminance combined additively with orientation and movement, suggesting that the salience system processes luminance somewhat independently of the two other features. On the other hand, orientation and movement together influenced salience underadditively, suggesting that these two features are processed nonindependently. This pattern of results suggests that the visual system does not sum sources of salience linearly, but treats some sources of salience as redundant.

     

Whichever way you choose to categorize, working memory helps you learn

There has been growing interest in the relationship between the capacity of a person's working memory and their ability to learn to categorize stimuli. While there is evidence that working memory capacity (WMC) is related to the speed of category learning, it is unknown whether WMC predicts which strategies people use when there are multiple possible solutions to a categorization problem. To explore the relationship between WMC, category learning, and categorization strategy use, 173 participants completed two categorization tasks and a battery of WMC tasks. WMC predicted the speed of category learning, but it did not predict which strategies participants chose to perform categorization. Thus, WMC does not predict which categorization strategies people use but it predicts how well they will use the strategy they select.     

Predictors of situational disengagement in the academic setting: The contribution of grades,perceived competence,and academic motivation

Background. Although psychological disengagement is a well‐documented phenomenon in the academic setting, the attempts to identify its predictors are scarce. In addition, existing research has mainly focused on chronic disengagement and less is known on the determinants of situational disengagement. Aims. The purpose of the present study was to identify the predictors of situational disengagement in a physical education (PE) setting. In line with the core postulate of psychological disengagement, it was hypothesized that grades contribute to discounting through a decrease in perceived competence. Drawing upon self‐determination theory, it was also expected that devaluing reflects the motivational orientations of individuals. Sample. A total of 120 students who were in seventh, eighth, and ninth grades. Method. Students were asked to report their motivation towards PE and their perceived competence at the beginning of a 10‐week cycle. Perceived competence in PE and psychological disengagement were assessed at the end of cycle, after grades were communicated individually to each student. Results. The results revealed that grades significantly predicted discounting, through perceived competence, but did not predict devaluing. Devaluing was negatively predicted by integrated and identified regulations, and positively predicted by amotivation, whereas no motivational variables were related to discounting. Conclusion. The present study extends the core postulate of psychological disengagement to situational disengagement. It revealed that students may temporarily disengage their self‐esteem from performance feedback through discounting, but are less inclined to devalue the academic domain when faced with negative feedback in a particular situation because of their motivational orientations.     

The effects of time perspective and level of construal on social distance

Psychological causes of social distance were examined from the perspective of Construal Level Theory (CLT; Liberman, Trope, & Stephan, 2007), which predicts that temporal distance from and abstract construal of a social target would create perception of social distance. Our studies demonstrate that expectations for temporally remote (versus proximal) social interaction produce greater social distance from a target person, measured as reduced familiarity (Study 1) and as reduced similarity to the self (Study 2). We also show that a more abstract, higher level construal of a social target results in less familiarity (Study 3) and in less allocation of resources (Study 4). The research sheds light on how social closeness can be promoted or hindered by previously unaddressed psychological factors.     

Comparison of non-suicidal self-injurious behavior and suicide attempts in patients admitted to a psychiatric crisis unit

The aim of the current study was to examine differences in personality, coping skills, and select psychopathology symptoms in psychiatric patients with and without non-suicidal self-injury and/or suicide attempts. We collected data in a sample of 128 psychiatric patients by means of self-report questionnaires measuring self-harm, psychological symptoms, personality and coping skills. Results support a continuum of self-harm such that patients with both non-suicidal self-injury and suicide attempts exhibit significantly greater levels of psychopathology and lower levels of adaptive personality traits and coping skills. The findings point to the clinical importance of making a distinction between non-suicidal self-injury and suicide attempts, and offers additional variables to consider outside of intent when appraising suicide risk.     

Sequential dependencies in recall of sequences: Filling in the blanks

Sequential dependencies can provide valuable information about the processes supporting memory, particularly memory for serial order. Earlier analyses have suggested that anticipation errors—reporting items ahead of their correct position in the sequence—tend to be followed by recall of the displaced item, consistent with primacy gradient models of serial recall. However, a more recent analysis instead suggests that anticipation errors are followed by further anticipation errors, consistent with chaining models. We report analyses of 21 conditions from published serial recall data sets, in which we observed a systematic pattern whereby anticipations tended to be followed by the “filling in” of displaced items. We note that cases where a different pattern held tended to apply to recall of longer lists under serial learning conditions or to conditions where participants were free to skip over items. Although the different patterns that can be observed might imply a dissociation (e.g., between short- and long-term memory), we show that these different patterns are naturally predicted by Farrell’s (Psychological Review 119:223–271, 2012) model of short-term and episodic memory and relate to whether or not spontaneously formed groups of items can be skipped over during recall.