Inhibition of the LH Surge by Restraint Stress in Cyclic Rats: Studies on the Role of GABAA and GABAB Receptors

There is evidence that stress can alter the activity in the brain of gamma-aminobutyricacid (GABA), a neurotransmitter that has been implicated in the regulation of LH secretion. In the present study the role of GABA in the restraint stress-induced inhibition of the LH surge was investigated in the intact cyclic rat. Intracerebroventricular (icv) administration of the GABAA receptor agonist muscimol (0.1, 0.5 or 1 μg) 5 min before the presumed onset of the pro-oestrous LH surge (at 0900 h) caused a dose dependent suppression of the surge. A single dose of the GABAB receptor agonist baclofen (1 μg; icv) injected at 0855 h postponed the onset of the LH surge, and repeated injections at 0855 and 1130 h suppressed the surge. These data indicate that GABA-ergic activity in the brain can inhibit the LH surge in the cyclic rat via GABAA and GABAB receptors. Pro-oestrous rats were subjected to 5 hrs of restraint starting at 0855 h. Pretreatment with the GABAA receptor antagonist bicuculine (1 μg; icv) at 0840, 0940 and 1040 h or pretreatment with the GABAB receptor antagonist phaclofen (10 μg; icv) at 0840 h were ineffective in preventing the restraint-induced inhibition of the LH surge. The results suggest that GABAA and GABAB receptors are not involved in the inhibitory effect of restraint stress on the LH surge.     

Mice with targeted genetic reduction of GABA(A) receptor alpha1 subunits display performance differences in Morris water maze tasks

Recent research has begun to demonstrate that specific subunits of GABA(A) receptors may be involved in the normal expression of specific behaviors. The present research used mice with GABA(A) receptors whose alpha1 subunits contained mutations of serine 270 to histidine and leucine 277 to alanine in the TM2 region. The purpose was an attempt to examine the possible role that this particular subunit may have in learning the spatial and nonspatial version of the Morris water maze task. Mutant animals, compared to controls, displayed elevated levels of pool circling in both the spatial task and the nonspatial task. These results suggested that normal performance of the spatial and nonspatial water maze tasks may be dependent upon a natural alpha1 subunit array.     

Antarctic skuas recognize individual humans

Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans.     

Egg White or Sun-Kissed: A Cross-Cultural Exploration of Skin Color and Women’s Leisure Behavior

The present study explores how culture-based meanings and values toward skin color, which are associated with women’s body image ideals and gender-role expectations, profoundly influence women’s leisure behaviors. Using in-depth interviews with East Asian, Asian American, and Euro-American women (n?=?43), results revealed how leisure behaviors are tied to cultural perceptions of skin color. People from different cultural backgrounds construct meanings and values pertaining to skin color, including beauty-related standards, social class, gender roles, and lifestyles. Culture-based values, such as the preference for tanned skin among Euro-Americans and for lighter skin among East Asians, affect a wide range of daily behaviors. These behaviors include conscious as well as subtle daily decision-making regarding sun-seeking, sun-avoidance, and sun-protection behaviors; indoor versus outdoor leisure participation; and appearance modifications. The study’s results add knowledge to how perceptions and attitudes toward skin color and appearance manifest in women's daily behavior in general and leisure behavior in particular. In addition, the current study shows how individual behaviors reflect cultural meanings and values toward body image, specifically skin color, by emphasizing the links between cultural values and women’s day-to-day lives.     

Yoga and Mindfulness: Clinical Aspects of an Ancient Mind/Body Practice

The use of Yoga and other complementary healthcare interventions for both clinical and non-clinical populations has increased substantially in recent years. In this context, we describe the implementation of Hatha Yoga in the Mindfulness-Based Stress Reduction (MBSR) program of Kabat-Zinn and colleagues. This is embedded in a more general consideration of Yoga’s place in complementary healthcare. In providing this overview, we comment on the nature and quality of current research on Yoga, summarize current physiological and psychological explanations of its effects, and discuss practical issues related to teacher training and experience.     

Family-Focused Relational Psychotherapy: An Integrative Approach and Its Application to Adult Children of Divorce

This paper presents an integrative model of treatment—family focused relational psychotherapy—and applies it to work with adult children of divorce (ACDs). Three areas of assessment are identified—(a) assessment of individual ego development, (b) assessment of family of origin functioning, and (c) assessment of the nature of the parents' divorce (e.g., level of conflict). Based on this assessment, the treatment model is presented, which integrates strategies from relational/psychodynamic therapy, family of origin work, and experiential techniques. Case examples are presented to demonstrate the appropriate integration of these techniques with clients at different levels in the assessment schema. In addition, a review of the literature on the long-term effects of divorce on children suggests several specific issues that may arise in treatment. These include low self-esteem, emotional distress, externalizing problems, and interpersonal problems such as fear of commitment, difficulty trusting, a high rate of divorce, and strained relationships with parents.     

Wild birds recognize individual humans: experiments on magpies, <Emphasis Type="Italic">Pica pica</Emphasis>

The ability to distinguish among heterospecific individuals has been reported in only a few animal species. Humans can be viewed as a special type of heterospecifics because individuals differ widely in behavior, ranging from non-threatening to very threatening toward animals. In this study, we asked whether wild magpies can recognize individual humans who had accessed their nests. We compared the behavior of breeding pairs toward individual humans before and after the humans climbed up to the birds’ nests, and also toward climbers and non-climbers. We have evidence for (i) aggressive responses of the magpie pairs toward humans who had repeatedly accessed their nests (climbers) and a lack of response to humans who had not accessed the nest (non-climbers); (ii) a total lack of scolding responses toward climbers by magpie pairs whose nests had not been accessed; (iii) a selective aggressive response to the climber when a climber and a non-climber were presented simultaneously. Taken together, these results suggest that wild magpies can distinguish individual humans that pose a threat to their nests from humans that have not behaved in a threatening way. The magpie is only the third avian species, along with crows and mockingbirds, in which recognition of individual humans has been documented in the wild. Here, we propose a new hypothesis (adopted from psychology) that frequent previous exposure to humans in urban habitats contributes to the ability of birds to discriminate among human individuals. This mechanism, along with high cognitive abilities, may predispose some species to learn to discriminate among human individuals. Experimental tests of these two mechanisms are proposed.     

Optische Untersuchungen am Ganzfeld

Ohne Zusammenfassung