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.     

Effects of Acute Stress or Centrally Injected Interleukin-1beta on Neuropeptide Expression in the Immune System

Acute stress stimulates the expression and release of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) from the hypothalamus, and the pro-opiomelanocortin products beta-endorphin and ACTH from the anterior pituitary. These neuropeptides are also expressed in immune tissues, and it has been proposed that they may modulate immune responses to stress through paracrine mechanisms. We subjected rats to restraint stress or central injection of interleukin (IL)-1beta to determine whether these acute stimuli can alter the expression of neuropeptides in the spleen and thymus. Restraint stress significantly increased the contents of all these neuropeptides in thymic, but not splenic, extracts. A single icv injection of IL-1beta increased contents of CRH, AVP, ACTH and beta-endorphin in the spleens of both sham-operated and adrenalectomised (ADX) rats. IL-1beta increased thymic contents of CRH and ACTH in sham-operated rats but these increases were not observed in ADX rats. These results suggest that the effects of IL-1beta on neuropeptide expression in the spleen are independent of glucocorticoids, whereas IL-1beta stimulation of neuropeptide expression in the thymus is dependent on circulating glucocorticoids. There were significant correlations between increases in CRH, ACTH and beta-endorphin in the spleen, and between CRH and ACTH in the thymus, consistent with the suggestion that IL-1beta-induced increases in ACTH and beta-endorphin may be mediated through CRH. These results provide evidence that stressors can directly influence neuropeptide expression in immune tissues. Thus stress may influence immune functions through paracrine mechanisms involving locally synthesised neuropeptides as well as through activation of the hypothalamo-pituitary-adrenal axis.     

Recognizing creative leadership: Can creative idea expression negatively relate to perceptions of leadership potential?

Drawing on and extending prototype theories of creativity and leadership, we theorize that the expression of creative ideas may diminish judgments of leadership potential unless the charismatic leadership prototype is activated in the minds of social perceivers. Study 1 shows that creative idea expression is negatively related to perceptions of leadership potential in a sample of employees working in jobs that required creative problem solving. Study 2 shows that participants randomly instructed to express creative solutions during an interaction are viewed as having lower leadership potential. A third scenario study replicated this finding showing that participants attributed less leadership potential to targets expressing creative ideas, except when the “charismatic” leader prototype was activated. In sum, we show that the negative association between expressing creative ideas and leadership potential is robust and underscores an important but previously unidentified bias against selecting effective leaders.     

大学二年级学生人际宽恕与报复心理及其与抑郁的关系研究

采用沉思量表、报复动机量表、宽恕倾向量表、宽恕态度量表和流调中心用抑郁量表对236名大二学生进行问卷调查,综合探讨大学生人际宽恕和报复心理及其与抑郁的关系。研究发现:(1)男大学生的报复倾向显著高于女大学生。(2)宽恕倾向与报复倾向及对侵犯的沉思程度显著负相关。沉思程度和抑郁显著正相关。(3)沉思程度和宽恕倾向对抑郁分别具有显著的正向和负向的预测作用。(4)大学生的宽恕倾向和宽恕态度的相互作用以及宽恕倾向和报复倾向之间的交互作用对抑郁均没有显著预测作用。     

Are two narcissists better than one? The link between narcissism, perceived creativity, and creative performance

The current research examines the link between narcissism and creativity at the individual, relational, and group levels of analysis. It finds that narcissists are not necessarily more creative than others, but they think they are, and they are adept at persuading others to agree with them. In the first study, narcissism was positively associated with self-rated creativity, despite the fact that blind coders saw no difference between the creative products offered by those low and high on narcissism. In a second study, more narcissistic individuals asked to pitch creative ideas to a target person were judged by the targets as being more creative than were less narcissistic individuals, in part because narcissists were more enthusiastic. Finally, a study of group creativity finds evidence of a curvilinear effect: Having more narcissists is better for generating creative outcomes (but having too many provides diminishing returns).     

Living large: the powerful overestimate their own height

In three experiments, we tested the prediction that individuals' experience of power influences their perceptions of their own height. High power, relative to low power, was associated with smaller estimates of a pole's height relative to the self (Experiment 1), with larger estimates of one's own height (Experiment 2), and with choice of a taller avatar to represent the self in a second-life game (Experiment 3). These results emerged regardless of whether power was experientially primed (Experiments 1 and 3) or manipulated through assigned roles (Experiment 2). Although a great deal of research has shown that more physically imposing individuals are more likely to acquire power, this work is the first to show that powerful people feel taller than they are. The discussion considers the implications for existing and future research on the physical experience of power.     

The bias against creativity: why people desire but reject creative ideas

People often reject creative ideas, even when espousing creativity as a desired goal. To explain this paradox, we propose that people can hold a bias against creativity that is not necessarily overt and that is activated when people experience a motivation to reduce uncertainty. In two experiments, we manipulated uncertainty using different methods, including an uncertainty-reduction prime. The results of both experiments demonstrated the existence of a negative bias against creativity (relative to practicality) when participants experienced uncertainty. Furthermore, this bias against creativity interfered with participants' ability to recognize a creative idea. These results reveal a concealed barrier that creative actors may face as they attempt to gain acceptance for their novel ideas.     

Can confidence come too soon? Collective efficacy,conflict and group performance over time

Groups with a strong sense of collective efficacy set more challenging goals, persist in the face of difficulty, and are ultimately more likely to succeed than groups who do not share this belief. Given the many advantages that may accrue to groups who are confident, it would be logical to advise groups to build a high level of collective efficacy as early as possible. However, we draw on Whyte’s (1998) theory of collective efficacy and groupthink, to predict that when confidence emerges at a high level toward the beginning of a group’s existence, group members may be less likely to engage in process conflict; a form of conflict that may be beneficial in the early phase of a group project. We found support for this prediction in two longitudinal studies of classroom project teams.     

Hidden consequences of the group-serving bias: Causal attributions and the quality of group decision making

A long stream of research in attribution theory suggests that groups are biased toward attributing their success to factors that are internal to their group. However, the existing research has confounded two types of attributions that are both internal to the group, but theoretically distinct: (1) attributions that differentiate between the contributions made by each individual group member and (2) attributions that focus on the group as a whole. This dichotomy is important because, drawing on theories of social influence, we predict that different types of attributions will have different consequences for the quality of group decision making. In Experiment 1, individually focused attributions for past success caused groups to consider more divergent alternatives prior to making a shared decision. In Experiment 2, individually focused attributions for past success facilitated the sharing of unique information and improved decision accuracy. These findings suggest that the group-serving tendency to internalize success may have important consequences for group performance that have not yet been considered in current research.     

Information processing bias against emotional facial expressions in social anxiety

The present study examined whether information processing bias against emotional facial expressions is present among individuals with social anxiety. College students with high (high social anxiety group; n  = 26) and low social anxiety (low social anxiety group; n  = 26) performed three different types of working memory tasks: (a) ordering positive and negative facial expressions according to the intensity of emotion; (b) ordering pictures of faces according to age; and (c) ordering geometric shapes according to size. The high social anxiety group performed significantly more poorly than the low social anxiety group on the facial expression task, but not on the other two tasks with the nonemotional stimuli. These results suggest that high social anxiety interferes with processing of emotionally charged facial expressions.