Central-place foraging by Rattus norvegicus on a radial maze

We studied central-place foraging in rats (Rattus norvegicus) by placing food items that varied in size and weight at the ends of a 4-arm radial maze. In Experiments 1-3, rats increasingly tended to carry food to the center of the maze as the size of those items increased. Very large food items often were hoarded in the center. Rats consumed food faster on the arms than in the center, and rats traveled faster when carrying food than when not. Blocking arm entrances increased travel time between the center and the arms and decreased food carrying at every item weight except the largest. In Experiments 4-6, important conditions that influence the degree of food-carrying behavior were discovered; these were the intersection of maze arms, the presence of a conspecific, and the use of open vs. closed maze arms.     

Perioral somatosensory determinants of nursing behavior in Norway rats (Rattus norvegicus)

Prior to assuming the upright crouching posture over their pups during nursing bouts, lactating rats typically engage in several oral behaviors, including nuzzling, licking and rearranging pups. By acutely depriving dams of various aspects of perioral stimulation from pups (with anesthesia of the mystacial pads or of the tongue, with mouth suturing, or with muzzling), we found the following: (1) Distal stimulation from pups maintains proximity-seeking behavior, but is insufficient to stimulate nursing behavior. (2) Lack of tongue feedback decreases pup licking and hastens the onset of crouching. (3) Snout, but not tongue, contact with pups is required for hovering over them. (4) The position of the dam while hovering over her litter enables the pups to gain access to her ventrum, thereby provoking her upright, crouching posture. (5) Older pups are capable of bypassing the dam's perioral attentions and stimulating crouching directly by burrowing under the dam's ventrum.     

Relationship of racial stressors to blood pressure responses and anger expression in black college students

The physiological effects of racism, as a stressor, were examined as they related to blood pressure (BP) and anger experiences in Black college students. Current research has failed to consider the stressful effects of racism as a factor contributing to the higher incidence of essential hypertension among Blacks. Twenty-seven Black college students viewed three excerpts showing racist situations involving Blacks; anger-provoking, nonracist situations; and neutral situations. After each scene, BP was taken, and a mood checklist was administered. The Framingham Anger Scale and the Anger Expression Scale were administered. Analyses revealed that BP significantly increased during the presentation of racist stimuli but not of anger-provoking or neutral stimuli. Self-reports of state anger, as measured by the mood checklist, were significant for both the anger-provoking and racist stimuli. BP scores were significantly correlated to the two trait anger measures. Exposure to racist stimuli was associated with BP increases among Blacks. Such cumulative exposure to racism may have important implications for the etiology of essential hypertension.     

Cross-sex comparisons: A word of caution

A cross-sex difference on one variable is often hypothesized to be related to a gender difference on a second variable. However, caution should be exercised in making such comparative hypotheses. We gathered the expected and actual examination grades for 168 female and 163 male college students. As in prior research, males had higher expectancies than females (p<.05). But analysis of the intrasex regression equations indicated that the relationship of expectancies to performance was different for women than it was for men. Thus, a cross-sex difference in expectancies did not correspond to a parallel difference in grades. This finding highlights the potential hazards of making certain cross-sex comparisons, and we argue for more caution in their application.     

Hugs or shrugs: Parental and peer influence on continuity of involvement in sport by female adolescents

The study was designed to examine the influence of significant others (mothers, fathers, and male and female peers) on continuing involvement in sport by adolescent females. Survey data were collected from 376 girls using a forced-choice, self-administered questionnaire. Maintenance of involvement was measured by the proportion of possible years in which the respondents were involved in physical activity within each of three participation contexts (intramural, interschool, and community sport). Several indicators of significant other influence were used. The degree to which involvement in physical activity is maintained is positively related to the source, amount and type of influence received from significant others, and varied by the participation context. Overall, the socializing influence of significant others was able to account for 11% of the variance in intramural activity, 20% of the variance in interschool sport, and 10% of the variance in community-based activity.This study was funded by a grant from Fitness Canada.     

The written summary in group psychotherapy revisited

This paper addresses the use of the weekly written summary with patients in group psychotherapy. In an effort to stimulate group process and effect cotherapist communication, the authors instituted this group recording in an ongoing psychodynamically oriented mixed adult group. While the utilization of this device did, in fact, stimulate the group process and became an important part of the group's life, the therapists additionally saw significant effects upon their working alliance. These included increased focused dialogue upon group dynamics, more purposeful planning for group interventions, and heightened awareness of the significance of interventions in the group.Ms. Bosman-Clark is formerly Clinical Instructor, Department of Psychiatry, Baylor College of Medicine.     

Brief group psychotherapy at retirement

Brief group psychotherapy as a method of treating psychological aftereffects of retirement is still in its infancy. It is therefore still possible to outline the whole field in overview. This paper examines the dynamics of aging and the relevant literature, discusses the conceptual issues involved, and describes techniques employed with this specific population. The typical cluster of complaints is portrayed, the psychological stressors associated with retirement are analyzed, and the various group-therapeutic modalities developed to counteract them are described. Furthermore, the rationale, process and characteristics of short-term group psychotherapy in the treatment of adjustment difficulties to retirement are reviewed. The clinical application of this approach, the therapist's particular roles and the therapeutic impact of this method are delineated.He would like to thank his co-therapist, Mrs. Sophie Bielawski, Reg. O.T., for her support and helpful observations and Drs. J. Regan and E. Sunday for their advice on methodolody.     

Overt integrity tests versus personality-based measures of delinquency: An empirical comparison

This study examined the ability of both an overt integrity test and a personality-based measure of delinquency to predict on-the-job theft and counterproductivity. A heterogeneous sample of 105 employees anonymously completed both tests and a criterion checklist that included a 9-item theft subscale and a 12-item counterproductivity subscale. Results indicated that the overt integrity test was a superior predictor of both on-the-job theft and drug abuse compared to the personality-based measure. The overt integrity test was also a slightly better predictor of general counterproductivity. These findings and their implications are discussed.     

The physiology of the tunnel

Several theories to account for the origin of tunnel hallucinations and tunnel experiences near death are considered: (1) the idea of a real tunnel; (2) representations of transition; (3) reliving birth memories; (4) imagination; and (5) physiological origins. Three different physiological theories are considered that related the tunnel form to the structure of the visual cortex. All can account for much of the phenomenology of the tunnel experience, and all lead to testable predictions. It is argued that the tunnel experience involves a change in the mental model of the self in the world. Because of this, an experience of purely physiological origin, with no implications for other worlds or for survival, can nevertheless produce lasting changes in the sense of self and reduce the fear of death.