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- Jönsson, Peter, et al.
(författare)
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Cardiovascular and cortisol reactivity and habituation to a virtual reality version of the Trier Social Stress Test: A pilot study.
- 2010
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Ingår i: Psychoneuroendocrinology. - : Elsevier BV. - 1873-3360 .- 0306-4530. ; 35, s. 1397-1403
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Tidskriftsartikel (refereegranskat)abstract
- The Trier Social Stress Test (TSST) is a widely used protocol to induce stress in laboratory settings. Briefly, in the TSST, the test participant is asked to hold a speech and to do an arithmetic task in front of an audience. In the present pilot study, we examined endocrine and autonomic reactivity and habituation to repeated stress provocations using a virtual reality (VR) version of TSST. The VR system was a CAVE system with three rear projected walls (4mx3m), and one floor projection. The system also included a head tracking system and passive stereoscopy. The virtual audience consisted of one woman, and two men. Ten healthy men, mean age 28.3 years (24-38 years), were confronted with the test twice (1 week between sessions), during which salivary cortisol, heart rate (HR), high frequency heart rate variability (HF-HRV, parasympathetic activity), and T-wave amplitude (TWA, suggested to be related to sympathetic influence on myocardial performance) were assessed. Cortisol secretion showed a marked increase (88% vs. baseline) during the first stress provocation, but habituated in the second session. The magnitude of HR and TWA reactivity during stress provocation was approximately the same at both sessions, implying a stable increase in sympathetic activity. Heart rate showed a maximum increase of 40% at the first session, and 32% at the second. TWA showed a maximum decrease of 42% at the first session, and 39% at the second. The results resemble those obtained in prior studies using the real-life TSST. If these results can be replicated with larger samples, VR technology may be used as a simple and standardized tool for social stress induction in experimental settings.
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| 23. |
- Jönsson, Peter, et al.
(författare)
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Exhaustion-related changes in cardiovascular and cortisol reactivity to acute psychosocial stress.
- 2015
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Ingår i: Physiology & Behavior. - : Elsevier BV. - 1873-507X .- 0031-9384. ; 151:Jul 22, s. 327-337
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Tidskriftsartikel (refereegranskat)abstract
- Prior findings indicate that individuals scoring high on vital exhaustion show a dysfunctional stress response (DSR), that is, reduced cortisol reactivity and habituation to psychosocial stressors. The main aim of the present study was to examine whether a DSR may be a vulnerability factor in exhaustion disorder (ED). We examined whether a DSR is present during the early stages of ED, and still is present after recovery. Three groups were studied: 1. Former ED patients (n = 14); 2. persons who during the past 6 month had experienced stress at work and had a Shirom-Melamed Burnout Questionnaire (SMBQ) score over 3.75, considered to indicate a pre-stage of ED (n = 17); 3. persons who had not experienced stress at work during the past 6 months and had a SMBQ score below 2.75 (n = 20). The participants were exposed twice to a virtual version of the Trier Social Stress Test (V-TSST), during which salivary cortisol samples were collected. In addition, high frequency heart rate variability (HF-HRV), heart rate (HR), t-wave amplitude (TWA), and alpha-amylase were assessed to examine stress reactivity and habituation in the autonomic nervous system (ANS). The initial analyses showed dear hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) activations in both V-TSST sessions, together with habituation of cortisol and heart rate in the second session, but without any significant group differences. However, the former ED patients showed considerable variation in self-reported signs of exhaustion (SMBQ). This led us to assign former ED patients with lower ratings into the low SMBQ group (LOWS) and those with higher ratings to the high SMBQ group (HIGHS). When repeating the analyses a different picture emerged; the HIGHS showed a lower cortisol response to the V-TSST than did the LOWS. Both groups' cortisol response habituated to the second V-TSST session. The ANS responses did not differ between the two groups. Thus, persons in a pre-stage of ED and unrecovered former ED patients showed signs of DSR, in contrast to healthy controls and recovered former ED patients. The results may be interpreted as indicating that DSR in the HPA axis is present early on in the stress process, but subsides after successful recovery. (C) 2015 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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