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.     

Bursting with anxiety: adult social referencing in an interpersonal balloon analogue risk task (BART)

This study developed an interpersonal modification of the balloon analogue risk task (BART) to assess effects of a friend's real-time facial expressions on coparticipants' risk-taking. Twenty pairs of male friends and 20 pairs of female friends completed two counterbalanced versions of BART, one framed in terms of monetary gain, and the other framed in terms of avoiding loss. Each pair included a player who performed the task across both trials and a reference person in a separate cubicle connected via a soundless video link. In the suppression condition, reference persons were told to minimize facial expressions of anxiety as balloons inflated. In the expression condition, they were told to freely express anxiety. As predicted, players took greater risks and burst more balloons in the suppression condition, but only under the gain frame. Players' BART scores across both frames were also significantly negatively correlated with reference persons' scores on a questionnaire measure of dispositional expressivity (BEQ), confirming that other people's expressions can moderate one's own risk-taking.     

Movement kinematics affect action prediction: comparing human to non-human point-light actions

The influence of movement kinematics on the accuracy of predicting the time course of another individual's actions was studied. A human point-light shape was animated with human movement (natural condition) and with artificial movement that was more uniform regarding velocity profiles and trajectories (artificial condition). During brief occlusions, the participants predicted the actions in order to judge after occlusion whether the actions were continued coherently in time or shifted to an earlier or later frame. Error rates and reaction times were increased in the artificial compared to the natural condition. The findings suggest a perceptual advantage for movement with a human velocity profile, corresponding to the notion of a close interaction between observed and executed movement. The results are discussed in the framework of the simulation account and alternative interpretations are provided on the basis of correlations between the velocity profiles of natural and artificial movements with prediction performance.     

How social is the social psychology of emotion?

Two classic studies published 50 years ago showed how other people provide information that shapes the activation and interpretation of emotions. The present paper traces development of the social psychology of emotions from this starting point. Subsequent research into group-based and social appraisal has advanced understanding of the impact of social information on emotions and suggested new ways of investigating associated phenomena. Although potential integrations of interpersonal and group-oriented approaches offer promise for the future, the continuing focus on emotions as cognitively mediated effects of social factors should broaden to encompass dynamic relational processes.     

Interpersonal effects of strategic and spontaneous guilt communication in trust games

A social partner’s emotions communicate important information about their motives and intentions. However, people may discount emotional information that they believe their partner has regulated with the strategic intention of exerting social influence. Across two studies, we investigated interpersonal effects of communicated guilt and perceived strategic regulation in trust games. Results showed that communicated guilt (but not interest) mitigated negative effects of trust violations on interpersonal judgements and behaviour. Further, perceived strategic regulation reduced guilt’s positive effects. These findings suggest that people take emotion-regulation motives into account when responding to emotion communication.     

Emotional and behavioural reactions to moral transgressions: cross-cultural and individual variations in India and Britain

Reactions to moral transgressions are subject to influence at both the cultural and individual levels. Transgressions against an individual's rights or against social conventions of hierarchy may elicit different reactions in individualistic and collectivistic cultures. In the current study, affective and behavioural reactions to transgressions of autonomy (rights) and community (hierarchy) were examined in India and Britain. Results revealed that although reactions to autonomy transgressions are similar in India and Britain, Indian participants express more moral outrage than do Britons in response to transgressions of community. Results also supported the contention of emotion‐specificity in affective moral reaction: Participants in both India and Britain reported anger in response to autonomy transgressions, but contempt in response to violations of community. Importantly, these results extend previous research by demonstrating the importance of emotion specificity in moral reactions, as opposed to categorization or dilemma resolution. In addition, an individual difference measure of respect for persons was shown to moderate reactions to moral transgressions. Specifically, participants with high respect for persons were less negative to violators of the community ethic, but not the autonomy ethic. These findings highlight the importance of examining emotion‐specific responses in the moral domain and introduce a significant individual difference variable, respect for persons, into the psychology of morality.     

Book reviews

John Christian Laursen (ed.). Religious Toleration: ‘The Variety of Rites’ from Cyrus to Defoe. New York, St Martin's Press, 1999. xx + 252 pp. $45.00. ISBN 0–312–22233–5.

Daniel Garber. Descartes Embodied: Reading Cartesian Philosophy through Cartesian Science Cambridge, Cambridge University Press, 2001, £40.00 hb; £14.95 pb. xii + 337 pp. ISBN 0–521–00337–7 pb. 0–521–80279–2 hb.

Olli Koistinen and John Biro (eds). Spinoza: Metaphysical Themes, Oxford, Oxford University Press, 2002. x + 255 pp. £40.00. ISBN 0–19–512815‐X.

Paul Abela. Kant's Empirical Realism. Oxford and New York, Clarendon Press, 2002. vii + 303 pp. £40.00. ISBN 0–19–924274–7.

Bruce L. Kinzer. England's Disgrace? J. S. Mill and the Irish Question. Toronto, Buffalo, and London, University of Toronto Press, 2001. 292 pp. $60. ISBN 0–8020–4862–5.

Maria Dimova‐Cookson. T. H. Green's Moral and Political Philosophy: A Phenomenological Perspective. Basingstoke, Palgrave, 2001. £40.00. xiii + 175 pp. ISBN 0–333–9144–7.

Stephen Mulhall. Inheritance &; Originality. Wittgenstein, Heidegger, Kierkegaard. Oxford, Clarendon Press, 2001. £40.00. xii + 448 pp. ISBN 0–19–924390–5.

Paul Gorner. Twentieth‐Century German Philosophy. Oxford, Oxford University Press, 2000. iii + 225 pp. £12.99. ISBN 0–19–289309–2.

Karen Green. Dummett: Philosophy of Language. Cambridge, Polity Press, 2001. xi + 236 pp. £55.00 (hb), £14.99 (pb). ISBN 0–7456–2294–1 (hb) 0–7456–2295‐X (pb).     

Language and knowledge in Spinoza

This paper argues against the thesis of Professor Savan, that Spinoza's views about words and about the imagination are such that he could not consistently say, and indeed did not think, that philosophical truths can be expressed adequately in language. The evidence for this thesis is examined in detail, and it is argued that Spinoza should have distinguished between two types of imagination, corresponding roughly to Kant's transcendental and empirical imagination. Finally, it is suggested that the bulk of the argument of the Ethics is conducted on the level of the ‘second kind of knowledge’, reason, but that it also contains examples of the use of the first and third kinds of knowledge.