The perception of surface curvature from optical motion

Observers viewed the optical flow field of a rotating quadric surface patch and were required to match its perceived structure by adjusting the shape of a stereoscopically presented surface. In Experiment 1, the flow fields included rigid object rotations and constant flow fields with patterns of image acceleration that had no possible rigid interpretation. In performing their matches, observers had independent control of two parameters that determined the surface shape. One of these, called the shape characteristic, is defined as the ratio of the two principle curvatures and is independent of object size. The other, called curvedness, is defined as the sum of the squared principle curvatures and depends on the size of the object. Adjustments of shape characteristic were almost perfectly accurate for both motion conditions. Adjustments of curvedness, on the other hand, were systematically overestimated and were not highly correlated with the simulated curvedness of the depicted surface patch. In Experiment 2, the same flow fields were masked with a global pattern of curl, divergence, or shear, which disrupted the first-order spatial derivatives of the image velocity field, while leaving the second-order spatial derivatives invariant. The addition of these masks had only negligible effects on observers’ performance. These findings suggest that observers’ judgments of three-dimensional surface shape from motion are primarily determined by the second-order spatial derivatives of the instantaneous field of image displacements.     

Group choice: competition, travel, and the ideal free distribution

If a group of foragers distributes among resource patches according to the ideal free distribution, the relative number of foragers in each patch should match the relative amount of resource obtained there, unless deviations arise from factors such as incomplete information or interforager interference. In analogy to individual choice, such effects may produce undermatching—group distribution falling short of resource distribution—or overmatching—group distribution overshooting resource distribution. In the present experiments, a flock of about 30 pigeons distributed between two patches with continuous inputs of green peas. Competition was varied by changing the size or extent of the patches. When the patches were areas or troughs, some undermatching occurred. When the patches were small bowls, strong undermatching occurred. When travel was required to switch patches, undermatching decreased slightly. A visual barrier that prevented pigeons from seeing one patch from the other had no effect. Overall rate of food delivery, varied over a wide range, had no effect. It appeared that the mechanism of flock distribution depended on comparisons between patches that were successive rather than simultaneous. Although most pigeons participated in the experiments, and different pigeons participated to different extents, individual pigeons tended to be consistent in the extent of participation from session to session, suggesting the possibility that participation might reflect competitive ability. Examination of the preferences and switching of individual pigeons revealed no consistency within or across individuals. It appeared that the flock's distribution was a truly emergent phenomenon, in the sense that results at the level of the flock in no way paralleled behavior at the level of the individual.     

A common factor in the MMPI scales of married couples.

Using canonical analysis, a common factor in the MMPI scales of husbands and wives was found. The Sc, Pd, and Hs scales for both the husbands and the wives contributed heavily to the relationship. Other scales contributing to the correlation between the personality components of the pairs were F, Hy Pt, and Si for the husbands and Pa for the wives. The results were interpreted as indicating areas of homogeneity and heterogeneity in the personalities of married couples.     

Testing the attentional model of brightness contrast with relative area and figure-ground organization unconfounded

Using gray-white metric patterns, for which figure-ground relationships had been previously determined, several features of an attentional theory of brightness contrast were investigated. Experiment I, involving three subjects and the method of constant stimuli, showed that ground, the unattended area, could be reliably perceived as brighter; responses were affected by both the type of pattern and level of contrast ratio. Experiment II, involving 40 subjects and the method of magnitude estimation, used metric patterns for which attentional factors were not confounded with relative area. The results supported the first study and further indicated the primary involvement of relative area rather than focus of attention in brightness contrast.

     

Self-Compassion and Predictors of Criminality

The main focus of this article is to conduct an exploratory investigation of self-compassion, a positive indicator of mental health, as a predictor of violence and criminality within a sample of prisoners. Correlation and regression analyses were used to explore the relationship that self-compassion has with self-control, self-esteem, and social connectedness. Associations between self-compassion and the subscales of self-control were also examined. Results from both correlational analysis and regression indicate that self-compassion is correlated with all 3 variables. Correlations revealed that self-compassion was related to all 6 subscales of self-control. Regression, however, revealed that impulsivity was the only predictor of self-compassion. Further analysis revealed problems with multicollinearity. Implications and limitations of these results are discussed.     

Cultural aspects of mental health and mental health service delivery with a focus on Nigeria within a global community

With an endless range of subgroups and individual variations, culture bears upon what all people bring to the clinical setting. Culture could account for health-seeking behaviour, type of services and support system and variations in how people communicate their health concerns. Culture may underlie presentation of sets of symptoms that are peculiar to certain societies – culture-bound syndromes. Culture also influences the meanings that people impart to their illness and also stigma associated with such illnesses. Culture must be viewed from the patients, clinicians and health system dimensions. Changes in mental health service delivery in last few decades have yielded culturally competent mental health services. The aim of this paper was to discuss culture and mental health with a focus on Nigeria and from a global perspective.     

Meta‐Analysis of Counseling Outcomes for the Treatment of Posttraumatic Stress Disorder

This meta‐analysis of 152 published posttraumatic stress disorder (PTSD) clinical trials from 1990 to 2012 concluded that counseling generally produced a small to large effect of treatment across all comparison conditions at termination (d+ = 0.30 to 0.89). These gains were maintained at longest follow‐up (d+ = 0.58 to 0.86) for the wait‐list, treatment‐as‐usual, and single‐group comparisons, but not for the follow‐up placebo comparison (d+ = 0.15), probably because of the low power (j = 3 placebo studies). Clinical trial findings were synthesized using a random‐effects model. No effects of publication bias or moderating variables were evident. No difference was found between trauma‐focused and non‐trauma‐focused approaches. Implications for counseling practice and future PTSD outcome research are addressed.     

Validation of a Brief Version of the Difficulties in Emotion Regulation Scale (DERS-18) in Five Samples

The field of affective clinical science has expanded dramatically over the past several decades (Rottenberg and Gross 2003; Tracy et al. 2014). An important part of this research is understanding emotion regulation and dysregulation, in particular, how individuals differ in their ability to identify, accept, and manage their emotional experiences. One of the most common and widely cited measures of emotion dysregulation is the Difficulties with Emotion Regulation Scale (DERS; Gratz and Roemer 2004), which has been extensively used to facilitate understanding of how emotion dysregulation is associated with psychiatric symptoms, other emotion-related constructs, and treatment progress. While this scale has contributed greatly to our understanding of emotion regulation problems, its length makes its inclusion in brief study protocols difficult, limiting its utility and increasing participant burden. In order to address this issue, we developed a short form version of the DERS (DERS-18) composed of the strongest items from each of the measure’s six subscales from the original DERS publication (Gratz and Roemer 2004), and then validated this measure in five datasets that vary in age and sample type. Our results demonstrate that an 18-item short-form of the DERS exhibits a similar structure as the original 36-item DERS, demonstrates excellent reliability and validity, and performs similarly to the original DERS despite comprising half the items. The DERS-18 has the potential to improve and expand emotion regulation assessment while reducing demands on research participants.