Psychoneuroendocrinology
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Psychoneuroendocrinology · Jan 2014
Randomized Controlled TrialAcute stress-induced cortisol elevations mediate reward system activity during subconscious processing of sexual stimuli.
Stress is thought to alter motivational processes by increasing dopamine (DA) secretion in the brain's "reward system", and its key region, the nucleus accumbens (NAcc). However, stress studies using functional magnetic resonance imaging (fMRI), mainly found evidence for stress-induced decreases in NAcc responsiveness toward reward cues. Results from both animal and human PET studies indicate that the stress hormone cortisol may be crucial in the interaction between stress and dopaminergic actions. ⋯ Although generally stress decreases activation in the NAcc in response to rewarding stimuli, high stress-induced cortisol levels suppress this relation, and are associated with stronger NAcc activation. Individuals with a high cortisol response to stress might on one hand be protected against reductions in reward sensitivity, which has been linked to anhedonia and depression, but they may ultimately be more vulnerable to increased reward sensitivity, and addictions. Future studies investigating effects of stress on reward sensitivity should take into account the severity of the stressor and the individual cortisol response to stress.
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Psychoneuroendocrinology · Dec 2013
Randomized Controlled TrialGiving peace a chance: oxytocin increases empathy to pain in the context of the Israeli-Palestinian conflict.
Studies have argued that empathy to the pain of out-group members is largely diminished by "in-group empathy bias". Investigating the mechanism underlying the emotional reactions of Jewish Israeli participants toward the pain experienced by Palestinians in the context of the Israeli-Palestinian conflict affords a natural experiment that allows us to examine the role of neurohormones in emotion sensitivity across conflicting social groups. ⋯ Oxytocin remarkably increased empathy to the pain of Palestinians, attenuating the effect of in-group empathy bias observed under the placebo condition. This effect, we argue, is driven by the general role of oxytocin in increasing the salience of social agents which, in turn, may interfere with processes pertaining to derogation of out-group members during intractable conflicts.
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Psychoneuroendocrinology · Nov 2013
Randomized Controlled TrialStress-induced negative mood moderates the relation between oxytocin administration and trust: evidence for the tend-and-befriend response to stress?
Recent evidence suggests that oxytocin, a nonapeptide posited to underlie the affiliation-related "tend-and-befriend" behavioral response to stress (Taylor et al., 2000), may improve interpersonal functioning by facilitating the acquisition of social support during times of distress. The assertion, however, has not been explicitly tested in humans. Thus, we examined whether the effect of oxytocin on self-perceived trust is magnified in individuals who experienced higher ratings of negative mood following social rejection. ⋯ These results demonstrate that oxytocin may promote the acquisition of social support in times of distress by increasing self-perceived trust. The findings provide empirical support that oxytocin promotes an affiliation-related behavioral response to stress, consistent with the tend-and-befriend theory.
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Psychoneuroendocrinology · Sep 2013
Randomized Controlled TrialReduction in salivary α-amylase levels following a mind-body intervention in cancer survivors--an exploratory study.
The main aim of this exploratory study was to assess whether salivary α-amylase (sAA) and salivary cortisol levels would be positively modulated by sleep-focused mind-body interventions in female and male cancer survivors. ⋯ In this exploratory study, sleep focused mind-body intervention (MBB) attenuated Waking sAA levels, suggesting positive influences of a mind-body intervention on sympathetic activity in cancer survivors with sleep disturbance.
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Psychoneuroendocrinology · May 2013
Randomized Controlled TrialChronicity of depressive problems and the cortisol response to psychosocial stress in adolescents: the TRAILS study.
Clinical and epidemiological studies, further supported by meta-analytic studies, indicate a possible association between chronicity (i.e., persistence or recurrence) of depression and hypothalamic-pituitary-adrenal (HPA) axis responsiveness to psychosocial stress. In the present study, we examined whether and how chronicity of depressive problems predicts cortisol responses to a standardized social stress test in adolescents. Data were collected in a high-risk focus sample (n=351) of the Tracking Adolescents' Individual Lives Survey (TRAILS) cohort, a large prospective population study with bi- to triennial measurements. ⋯ Chronicity of depressive problems was significantly associated with cortisol stress responses. The relationship was curvilinear, with recent-onset depressive problems predicting an increased cortisol response, and more chronic depressive problems a blunted response. The results of this study suggest that depressive problems initially increase cortisol responses to stress, but that this pattern reverses when depressive problems persist over prolonged periods of time.