Golden hamsters on the eight-arm maze in light and darkness: The role of dead reckoning

This paper examines whether golden hamsters can rely on dead reckoning (getting positional information from updated signals generated during locomotion) on an eight-arm maze. Two groups of hamsters were tested: Group L under ordinary room light, Group D in darkness. To enhance the role of dead reckoning, each subject could climb from its own home cage onto the central platform of the maze. In a first experimental phase (15 trials), the L subjects learned to master the maze through developing a locomotor rule (arm chaining) after three to four trials. The D subjects developed arm chaining less readily and fluctuated more in their performance than did the L subjects. In a second experimental phase (15 trials), four arms were blocked at the beginning of each trial. In both experimental groups the performance decreased, yet remained well above chance level. Success and arm chaining were positively correlated in Phase 1 and negatively correlated with success in Phase 2. We assume that in Phase 2 the L subjects switched to the predominant use of visual cues, and the D subjects to dead reckoning.     

Perceiving Necessity

In many diagrams one seems to perceive necessity – one sees not only that something is so, but that it must be so. That conflicts with a certain empiricism largely taken for granted in contemporary philosophy, which believes perception is not capable of such feats. The reason for this belief is often thought well‐summarized in Hume's maxim: ‘there are no necessary connections between distinct existences’. It is also thought that even if there were such necessities, perception is too passive or localized a faculty to register them. We defend the perception of necessity against such Humeanism, drawing on examples from mathematics.     

The Use of Risk and Need Factors in Forensic Mental Health Decision-Making and the Role of Gender and Index Offense Severity

Canadian legislation makes Review Boards (RBs) responsible for rendering dispositions for individuals found Not Criminally Responsible on account of Mental Disorder (NCRMD) after considering public safety, the mental condition of the accused, and his/her potential for community reintegration. We reviewed 6,743 RB hearings for 1,794 individuals found NCRMD in the three largest Canadian provinces to investigate whether items from two empirically supported risk assessment measures, the Historical Clinical Risk Management-20 and the Violence Risk Appraisal Guide, were considered. Less than half the items were included in expert reports or in RBs' reasons for dispositions, and consideration of these items differed according to gender and index offense severity of the accused. These items included evidence-based risk factors and/or legally specified criteria: mental health, treatment, and criminal history. These results illustrate the gap between research on risk factors and the integration of this evidence into practice. In particular, we recommend the implementation of structured measures to reduce the potential for clinicians to be unduly influenced by gender and offense severity. Copyright © 2015 John Wiley & Sons, Ltd.     

WOMEN'S HOSTILITY TOWARD WOMEN

Three studies investigating the self-report correlates of women's hostility toward other women were conducted among a total of 477 college women. In Study 1, hostility toward women was negatively associated with both personal and collective self-esteem and positively associated with hostility toward men, controlling for state anger. In Study 2, hostility toward women was negatively associated with self-efficacy and age and positively associated with emotional dependence on men, but not with self-identification as a feminist or support of the feminist movement. In Study 3, women's hostility toward women was negatively associated with measures of intimacy and life satisfaction and positively associated with acceptance of interpersonal violence. We suggest that women's hostility toward other women not only is an important aspect of women's personal satisfaction, happiness, intimacy, and self-esteem, but also may serve as a barrier to women's progress as a group.     

Intersection crossing considered as intercepting a moving traffic gap: Effects of task and environmental constraints

Safely crossing an intersection requires that drivers actively control their approach to the intersection with respect to characteristics of the flow of incoming traffic. To further our understanding of the perceptual-motor processes involved in this demanding manoeuvre, we designed a driving simulator experiment in which 13 participants actively negotiated intersections by passing through a gap in the train of incoming traffic. Task constraints were manipulated by varying the size of the traffic gap and the initial conditions with respect to the time of arrival of the traffic gap at the intersection. Environment constraints were manipulated by varying the intersection geometry through changes in the angle formed by the crossroads. The results revealed that the task constraints systematically gave rise to continuous and gradual adjustments in approach velocity, initiated well before arriving at the intersection. These functionally appropriate adjustments allowed the drivers to safely cross the intersection, generally just slightly ahead of the center of the traffic gap. Notwithstanding the fact that the geometry of the intersection did not affect the spatiotemporal constraints of the crossing task, approach behavior varied systematically over geometries, suggesting that drivers rely on the traffic gap's bearing angle. Overall, the pattern of results is indicative of a continuous coupling between perception and action, analogous to that observed in locomotor interception tasks.