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New paper out on the stability and durability of salivary alpha-amylase across different storage conditions

Data collection in remote and field settings gains importance and popularity in stress research. Accordingly, existing stress induction paradigms have been successfully adapted to remote and field settings. However, guidelines for the comprehensive assessment of biomarkers such as salivary alpha-amylase (sAA) have yet to be sufficiently established for such contexts. In remote and field settings, swift freezing of saliva samples is not always possible, and samples must be returned to the laboratory for further processing. The current study investigated the robustness of sAA activity against external factors that may affect measurements obtained from saliva samples collected in field and remote settings. We compared sAA activity of samples that were stored in different vials (Salivettes® and Eppendorf® vials) and that were exposed to (1) up to three cycles of freezing and thawing, (2) different temperatures (4 °C, 20 °C, 30 °C, and 40 °C) for 3, 7, 14, or 28 days, or that were (3) sent via postal delivery. Results indicate sAA activity to be susceptible across different temperatures, different time intervals, and different vials. As a systematic pattern, sAA activity seems to decrease in treated samples with this effect being potentiated by more extreme conditions such as higher temperatures and longer time intervals. To conclude, sAA data collected in remote or field settings could be affected systematically by various external variables. Future studies collecting sAA should take factors influencing the durability and stability of sAA into account to ensure reliable and valid measurements of salivary data.

The full citation of the new paper is: Heyers, K., Pfeifer, L. S., Walusiacki, K., Reinke, P., Moser, D., Ocklenburg, S., & Wolf, O. T. (2023). Stability and Durability of Salivary Alpha-Amylase across Different Storage Conditions. Psychoneuroendocrinology, 161, 106929.

 

New paper on the timing-dependent impact of cortisol on the neural correlates of emotion regulation

Dynamic functions of stress hormones for the cognitive control of emotions over time via non-genomic and genomic cortisol effects were investigated in this randomized, double-blind, placebo-controlled neuroimaging experiment. Participants received 20 mg hydrocortisone (cortisol) or a placebo either 30min (rapid, non-genomic cortisol effects) or 90min (slow, genomic cortisol effects) prior to a cognitive reappraisal task including different regulatory goals (i.e., downregulate vs. upregulate negative emotions). On the behavioral level, cortisol rapidly reduced and slowly enhanced emotional responsivity to negative pictures. However, only slow cortisol effects improved downregulation of negative emotions. On the neural level, cortisol rapidly enhanced, but slowly reduced amygdala and dorsolateral prefrontal activation as well as functional connectivity between both structures in the down- minus upregulate contrast. This interaction speaks for an effortful but ineffective regulation of negative emotions during rapid cortisol effects and improved emotion regulation capacities during slow cortisol effects. Taken together, these results indicate a functional shift of cortisol effects on emotion regulation processes over time which may foster successful adaptation to and recovery from stressful life events.

The full citation of the new paper is: Pan, D., Jentsch, V.L., Langer, K., Hagedorn, B., Höffken, O., Wolf, O.T. & Merz, C.J. (2023). What a difference timing makes: Cortisol effects on neural underpinnings of emotion regulation. Neurobiology of Stress, 25, 100544. Our work was supported by the Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) within the SFB 1280 Extinction Learning.

Christian Merz re-elected as Committee Member of the Board and Treasurer in the Section Biological Psychology and Neuropsychology of the German Psychological Society

After two years, Christian was successfully re-elected to further serve as Committee Member of the Board and Treasurer in the Section Biological Psychology and Neuropsychology of the German Psychological Society. Further Committee Members are Tina Lonsdorf (Bielefeld), Nina Alexander (Marburg), Matthias Sperl (Giessen) and Helena Hartmann (Essen).

New paper on rapid stress effects on emotion regulation performances

Acute stress activates the sympathetic nervous system (SNS) and the hypothalamus-pituitary-adrenal (HPA) axis leading to the release of (nor)-adrenaline and cortisol, respectively. Previous research demonstrated that acute stress may either enhance or impair cognitive emotion regulation (ER) performances. Besides sex and emotion intensity, another moderating factor might be the predominant stress system. Whereas increases in the stress hormone cortisol has been associated with regulatory improvements, early physiological responses of the SNS might impair ER performances. To test this hypothesis, we investigated whether and how acute stress rapidly modifies the ability to deal with negative emotions via two strategies: reappraisal and distraction. Affective ratings and pupil dilations served as regulatory outcome measures. Increases in salivary cortisol, heart rate / blood pressure (cardiovascular activity) and negative affect verified successful induction of acute stress via the Socially Evaluated Cold-Pressor Test. As opposed to previous expectations, stress reduced subjective emotional arousal when men distracted themselves from negative pictures. This effect was especially pronounced in the second half of the paradigm (20-30min after stress onset) and critically mediated by somewhat delayed rising cortisol levels. These results suggest beneficial stress effects on distraction in men to be driven by glucocorticoids. In contrast, rapid cardiovascular reactivity (index of the SNS) was linked to reduced regulatory performances of reappraisal and distraction in women. Taken together, our findings provide first evidence for rapid, opposing effects of the two stress systems on the cognitive regulatory control of negative emotions in dependence of sex.   

The full citation of the new paper is:
Langer, K., Jentsch, V. L., & Wolf, O. T. (2023). Rapid effects of acute stress on cognitive emotion regulation. Psychoneuroendocrinology, 151, 106054. https://doi.org/10.1016/j.psyneuen.2023.106054
Our work was supported by the Deutsche Forschungsgemeinschaft (DFG; German Research Foundation; Project WO 733/15-1).

New paper on the influence of rapid and delayed stress effects on the recognition of faces

In the previous literature, stress has mainly been described as a negative influencing factor in the context of episodic memory recognition. However, these findings mostly rely on the processing of words and images of objects or situations, while face recognition has hardly been studied. In the present study, we investigated the rapid and delayed effects of stress on the recognition of female and male faces with different emotional facial expressions. For this purpose, participants had to learn a series of face stimuli on the first day to be able to recognize and distinguish them from additional new face stimuli about 24 hours later. Divided into two different groups, participants either had to undergo a psychophysiological stress situation or a control condition before carrying out recognition tasks at two different time points (25 minutes after stressor/control onset and 90 minutes after stressor/control onset). Surprisingly, recognition performance was better in the stress than in the control group. This result was evident for both the rapid and the delayed recognition phase, with female faces in particular being better remembered during the rapid recognition phase. These results suggest that the influence of stress on recognition performance is more complex than previously assumed. It leads to the presumption that stress effects operate in a long time window and that simple alterations in stimulus material, the intensity of the stressor or the context of the study can result in opposite stress effects on memory recognition.

The full citation of the new paper is:
Pötzl, L., Wolf, O.T., Merz, C.J. (2023): Rapid and delayed stress effects on recognition of female and male faces. Psychoneuroendocrinology, 150, 106043. DOI: 10.1016/j.psyneuen.2023.106043.
The study was funded by the German Research Foundation (ME 3831/5-1) and published in the journal Psychoneuroendocrinology.