2023-09, Dimitroff, Stephanie J., Würfel, Lisa, Meier, Maria, Faig, Kelly E., Benz, Annika B. E., Denk, Bernadette F., Bentele, Ulrike U., Unternaehrer, Eva, Pruessner, Jens C.

To date, 72 % of the world’s population has received at least one COVID-19 vaccination. The number of antibodies produced by some individuals is exponentially higher than in others, for various mostly unknown reasons. This variation causes great diversity in the future susceptibility to infection by the original or variants of the SARS-CoV-2 virus. The following study investigated whether individuals were able to estimate the strength of their antibody response after their COVID-19 vaccinations. 166 recently vaccinated participants provided a blood sample for determination of antibody titers. Participants were asked to estimate how many antibodies they thought they had produced, and were further asked how protected they felt from COVID-19 due to vaccination. Both self-rated antibody levels, and feelings of protection against COVID-19 were significantly related to their actual IgG spike antibody titers, after controlling for age, days since vaccination, BMI and cross vaccination. These results suggest that individuals may have a form of “immune interoception” which relates to their response to their COVID-19 vaccination.

2022-05-30, Meier, Maria, Haub, Kristina, Schramm, Marie-Luise, Hamma, Marc, Bentele, Ulrike U., Dimitroff, Stephanie J., Gärtner, Raphaela, Denk, Bernadette F., Benz, Annika B. E., Unternaehrer, Eva, Pruessner, Jens C.

The Trier Social Stress Test (TSST) is a reliable and efficient protocol to induce acute psychosocial stress in the laboratory. If circumstances do not allow in-person assessments, an online version of the TSST could create more flexible research opportunities. To date, studies have confirmed subjective and autonomic stress responses to online TSST protocols. In this preregistered study (https://osf.io/u57aj), we focused on the effect of a TSST online for adults (TSST-OA) on cortisol and alpha amylase levels, and pleasure and arousal ratings. As cortisol stress reactivity is mediated by sex, we further compared men and women. We hypothesized significant increases in cortisol, alpha amylase and arousal, and a decrease in pleasure in response to the TSST-OA. Also, we expected stronger cortisol responses in males as compared with females, as in the laboratory TSST. N = 48 adults (56% female, meanage=23.02 years, SD=3.19) participated in the study. Saliva sampling devices were sent to participants' home before testing sessions, during which the experimenter, a mixed-sex panel, and the participant joined a video call. Participants underwent the TSST-OA and overall provided five saliva samples for cortisol and alpha amylase detection. Pleasure and arousal ratings and psychometric questionnaires were also completed online. As hypothesized, the TSST-OA significantly increased cortisol, alpha amylase, and arousal levels, while it decreased pleasure. Moreover, cortisol responses were significantly stronger in males as compared to females. 64% of subjects were classified as responders (cortisol rise>1.5nmol/l). The TSST-OA successfully induced psychophysiological stress in adults. Our protocol offers new possibilities to study stress outside of the laboratory.

2021-10-20, Meier, Maria, Bentele, Ulrike U., Benz, Annika B. E., Denk, Bernadette F., Dimitroff, Stephanie J., Pruessner, Jens C., Unternaehrer, Eva

The stress response supports survival through energy mobilization. Paradoxically, a low blood glucose level dampens the endocrine stress response, and sugar consumption prior to stress restores it. Thus, energy availability may play a causal role in the endocrine stress response. Yet, it has never been tested whether sweet taste or expectations towards a drink content modulate the stress response. We investigated the potential role of sweetness, energy load and expectations towards energy load of a drink consumed prior to stress in restoring stress reactivity after fasting. N=152 women (meanage=21.53, sdage=2.61) participated in the Trier Social Stress Test for groups in the morning after an overnight fast. Prior to stress induction, participants consumed a drink containing saccharose (sugar, n=51), an equally sweet drink containing non-caloric sweetener (sweetener, n=46), or water (n=56). Additionally, participants in the sugar and sweetener group (n=97) were informed whether or not their drink contained any calories (energy prime), which was deceptive in 50% of the cases. Eight salivary cortisol (-30, -20, -10, 0, +12, +25, +35, +45 min) and three blood glucose samples (-30, 0, +25 min) were assessed throughout the experiment. The effects of the experimental manipulations on cortisol trajectories were tested using multilevel mixed models. We found that compared with water, sugar and sweetener both significantly increased cortisol stress reactivity and with comparable intensity. However, our sensitivity analysis revealed a significant effect of sugar on cortisol trajectories compared to water and to sweetener. Drink-induced changes in blood glucose concentration were not associated with increases in cortisol. The energy prime did not affect the stress response. Overall, we could replicate the boosting effect of sugar consumption in a female sample after 8 h of fasting. The specific contribution of sweet taste and metabolic hormones to this boosting effect should be tested more rigorously in sex-balanced designs in the future.

2021-09, Bentele, Ulrike U., Meier, Maria, Benz, Annika B. E., Denk, Bernadette F., Dimitroff, Stephanie J., Pruessner, Jens C., Unternaehrer, Eva

Individuals with a history of low maternal care (MC) frequently present a blunted, yet sometimes also show an increased cortisol stress response. Fasted individuals with low blood glucose levels who are exposed to acute stress typically show an attenuated response pattern in this endocrine marker. Despite well-documented metabolic dysregulations after low MC, a possible interaction of both factors has not been investigated yet. Here, we examined the effects of MC and blood glucose concentration on various aspects of the stress response. Fasted women (N = 122, mean_age = 22.12, sd_age = 2.56) who experienced either very high, high, or low MC (based on the Parental Bonding Instrument) were randomly assigned to consume grape juice (condition sugar), or water (condition water) prior to being exposed to the Trier-Social-Stress-Test for groups. Salivary cortisol and alpha amylase, blood glucose, and mood ratings were assessed repeatedly. Using multilevel mixed models, we replicated the boosting effect of glucose on the cortisol stress response. While we found neither an effect of MC, nor an interaction between MC and blood glucose availability on the cortisol stress response, we observed an effect of MC on the amylase stress response. We discuss the results in the light of links between various stress/energy systems that possibly mediate health-related MC effects.

2023-03-11, Benz, Annika B. E., Dimitroff, Stephanie J., Jeggle, Christin, Gaertner, Raphaela J., Meier, Maria, Unternaehrer, Eva, Bentele, Ulrike U., Denk, Bernadette F., Klink, Elea S. C., Pruessner, Jens C.

While many studies investigated basic facets of empathy, less is known about the association with early life adversity (ELA). To investigate a possible association of empathy with ELA, we assessed self-reported ELA, using the Childhood Trauma Questionnaire (CTQ), the Parental Bonding Instrument (PBI) for mother and father, and empathy, using the Interpersonal Reactivity Index (IRI), in a sample of N  = 228 (83% female, age mean  = 30.51 ± 9.88 years, age range  = 18–60). Further, we measured willingness to donate a certain percentage of study compensation to a charity as an index of prosocial behavior. In line with our hypotheses that stated a positive association of empathy with ELA, increased levels of emotional, physical, and sexual abuse, and emotional and physical neglect were positively correlated with personal distress in response to others’ suffering. Likewise, higher parental overprotection and lower parental care were related to higher personal distress. Furthermore, while participants with higher levels of ELA tended to donate more money on a merely descriptive level, only higher levels of sexual abuse were significantly related to larger donations after correction for multiple statistical tests. Other facets of the IRI (empathic concern, perspective taking and fantasy) were not related to any other ELA measure. This suggests ELA only affects levels of personal distress.

2022, Benz, Annika B. E., Gärtner, Raphaela, Meier, Maria, Unternaehrer, Eva, Scharndke, Simona, Jupe, Clara, Wenzel, Maya, Bentele, Ulrike U., Dimitroff, Stephanie J., Denk, Bernadette F., Pruessner, Jens C.

Growing evidence suggests that natural environments - whether in outdoor or indoor settings - foster psychological health and physiological relaxation, indicated by increased wellbeing, reduced stress levels, and increased parasympathetic activity. Greater insight into differential psychological aspects modulating psychophysiological responses to nature-based relaxation videos could help understand modes of action and develop personalized relaxation interventions. We investigated heart rate variability (HRV) as an indicator of autonomic regulation, specifically parasympathetic activity, in response to a 10-min video intervention in two consecutive studies as well as heart rate (HR). We hypothesized that a nature-based relaxation video elicits HRV increase and HR decrease, with response magnitude being affected by aspects of early life adversity (conceptualized as low parental care and high overprotection/constraint) and trait mindfulness. In Study 1, N = 60 participants (52% female, age mean = 23.92 ± 3.13 years, age range = 18-34 years) watched a relaxation video intervention depicting different natural scenery. We analyzed changes in HR and respiratory sinus arrhythmia (RSA) as a standard HRV measure, both based on 3-min segments from the experimental session, in multiple growth curve models. We found a decrease in HR and increase of RSA during the video intervention. Higher paternal care and lower trait mindfulness observing skills (assessed via questionnaires) were associated with higher RSA values before but not during video exposure. In Study 2, N = 90 participants (50% female, age mean = 22.63 ± 4.57 years, age range = 18-49 years) were assigned to three video conditions: natural scenery from Study 1, meditation video, or short clip from "The Lord of the Rings." Again, HR decreased, and RSA increased during video segments, yet without expected group differences across different video types. We found higher parental care and lower parental overprotection to predict higher RSA at different times during the experiment. Interestingly, lower paternal overprotection predicted overall higher RSA. These results suggest a generic relaxation effect of video interventions on autonomic regulation that we discuss in light of different theories mapping restorative effects of natural environments. Further, psychological characteristics like aspects of early life adversity and trait mindfulness could contribute to individual differences in autonomic regulation. This study contributes to a better understanding of autonomic and psychological responses to relaxation videos.

2021-09-16, Carleial, Samuel, Nätt, Daniel, Unternaehrer, Eva, Elbert, Thomas, Robjant, Katy, Wilker, Sarah, Vukojevic, Vanja, Kolassa, Iris-Tatjana, Rukundo-Zeller, Anja C., Koebach, Anke

The aftermath of traumatization lives on in the neural and epigenetic traces creating a momentum of affliction in the psychological and social realm. Can psychotherapy reorganise these memories through changes in DNA methylation signatures? Using a randomised controlled parallel group design, we examined methylome-wide changes in saliva samples of 84 female former child soldiers from Eastern DR Congo before and six months after Narrative Exposure Therapy. Treatment predicted differentially methylated positions (DMPs) related to ALCAM, RIPOR2, AFAP1 and MOCOS. In addition, treatment associations overlapped at gene level with baseline clinical and social outcomes. Treatment related DMPs are involved in memory formation—the key agent in trauma focused treatments—and enriched for molecular pathways commonly affected by trauma related disorders. Results were partially replicated in an independent sample of 53 female former child soldiers from Northern Uganda. Our results suggest a molecular impact of psychological treatment in women with war-related childhood trauma.

2023, Cost, Katherine T., Unternaehrer, Eva, Tsujimoto, Kimberley, Vanderloo, Leigh L., Birken, Catherine S., Maguire, Jonathon L., Szatmari, Peter, Charach, Alice

Digital media screens have become an essential part of our family life. However, we have insufficient knowledge about parental screen use patterns and how these affect children's socio-emotional development. In total, 867 Canadian parents of 5-year-old children from the TARGet Kids! Cohort (73.1% mothers, mean ± SD age = 38.88 ± 4.45 years) participated in this study from 2014 to the end of 2019. Parents reported parental and child time on television (TV) and handheld devices and completed the Strengths and Difficulties Questionnaire (SDQ). Latent profile analysis identified six latent profiles of parent screen use: low handheld users (P1, reference; n = 323), more TV than handheld (P2; n = 261), equal TV and handheld (P3; n = 177), more handheld than TV (P4; n = 57), high TV and handheld (P5; n = 38), and extremely high TV and handheld (P6; n = 11). Parents that were more likely to belong to P6 were also more likely to be living in single-parent households compared to P1 (estimate = −1.49 ± 0.70), p = .03). High membership probability for P2 (estimate = −0.67 ± 0.32, p = .04) and P4 (estimate = −1.42 ± 0.40, p < 0.001) was associated with lower household income compared to P1. Children of parents with higher P4 (χ2 = 12.32, p < 0.001) or P5 (χ2 = 9.54, p = .002) membership probability had higher total screen time compared to P1. Finally, a higher likelihood to belong to P6 (χ2 = 6.82, p = .009) was associated with a higher SDQ Total Difficulties Score compared to P1. Thus, patterns of parent screen use were associated with child screen use and child socio-emotional problems. The emerging link between parental screen use profiles and child behaviors suggests the need for more research on parent screen time.

2022, Benz, Annika B. E., Kloker, Liliane Vanessa, Kuhlmann, Tim, Meier, Maria, Unternaehrer, Eva, Bentele, Ulrike U., Dimitroff, Stephanie J., Denk, Bernadette F., Reips, Ulf-Dietrich, Pruessner, Jens C.

Das elterliche Erziehungsverhalten beeinflusst sowohl die Entwicklung eines Kindes als auch die Entstehung und Behandlung psychischer Störungen. Das Parental Bonding Instrument (PBI; Parker, Tupling & Brown, 1979) ist ein bekanntes Instrument zur retrospektiven Erfassung des elterlichen Erziehungsstils. Bisher existiert jedoch keine ausreichend validierte deutsche Version. Daher entwickelten wir eine sprachlich aktuelle, deutsche Übersetzung des PBI (PBI-dt) und untersuchten in einer Onlinestudie anhand einer deutschsprachigen Stichprobe (N=791) die psychometrischen Eigenschaften des PBI-dt hinsichtlich Item- und Reliabilitätskennwerten, Konstrukt- und Kriteriumsvalidität sowie der faktoriellen Struktur. Die Analysen ergaben gute Item- und Reliabilitätskennwerte (α=0,86−0,95). Die Skalen des PBI korrelierten in den erwarteten Richtungen mit den Skalen des Childhood Trauma Questionnaire (CTQ). Außerdem wurden signifikante Unterschiede im berichteten elterlichen Erziehungsstil zwischen Personen mit und ohne psychische Erkrankung sowie zwischen übergewichtigen und normalgewichtigen Personen gefunden. Diese Ergebnisse weisen auf das Vorliegen von hoher Konstrukt- und Kriteriumsvalidität hin. Konfirmatorische Faktorenanalysen ergaben in allen untersuchten Fitindizes eine akzeptable Modellanpassungsgüte sowohl für das 2-Faktorenmodell von Parker et al. (1979) als auch für das 3-Faktorenmodell mit den Subskalen FürsorgeFürsorgeFürsorgeFürsorgeFürsorgeFürsorge, Einschränkung der VerhaltensfreiheitEinschränkung der VerhaltensfreiheitEinschränkung der VerhaltensfreiheitEinschränkung der VerhaltensfreiheitEinschränkung der VerhaltensfreiheitEinschränkung der Verhaltensfreiheit sowie Verweigerung psychologischer AutonomieVerweigerung psychologischer AutonomieVerweigerung psychologischer AutonomieVerweigerung psychologischer AutonomieVerweigerung psychologischer AutonomieVerweigerung psychologischer Autonomie. Die Verwendung einer 3-Faktorenstruktur konnte zudem inhaltlichen Mehrwert bieten, z. B. eine bessere Differenzierung zwischen normal- und übergewichtigen Personen. Insgesamt weist die vorliegende deutsche Übersetzung des PBI somit gute psychometrische Eigenschaften auf und stellt ein reliables Messinstrument dar.

2021-09, Denk, Bernadette F., Dimitroff, Stephanie J., Meier, Maria, Benz, Annika B. E., Bentele, Ulrike U., Unternaehrer, Eva, Popovic, Nathalie F., Gaissmaier, Wolfgang, Pruessner, Jens C.

Physiological synchrony (PS) is defined as the co-occurrence and interdependence of physiological activity between interaction partners. Previous research has uncovered numerous influences on the extent of PS, such as relationship type or individual characteristics. Here, we investigate the influence of acute stress on PS. We do so in a setting in which PS was not promoted, but contact between group members was explicitly minimized. We reanalyzed cortisol, alpha-amylase, and subjective stress data from 138 participants (mean age = [Formula: see text], 47.1% female) who previously underwent the Trier Social Stress Test for groups (TSST-G) or a non-stressful control task together, collected as part of a larger project by Popovic et al. (Sci Rep 10: 7845, 2020). Using a stability and influence model, an established method to test for synchrony, we tested whether individuals' cortisol and alpha-amylase concentrations could be predicted by group members' levels. We found cortisol PS in participants who were in the same group, the extent of which was stronger in the non-stressful control condition. For alpha-amylase, participants were synchronized as well; furthermore, there was an interaction between previous stress levels and PS. This suggests that while synchrony of both stress markers can occur in group settings even with spurious interaction, stressor exposure might attenuate its extent. We argue that if PS occurs in a sample where interaction was minimal, the phenomenon might be more widespread than previously thought. Furthermore, stressor exposure might influence whether a situation allows for PS. We conclude that PS should be investigated within group settings with various degrees of social interaction to further expose mechanisms of and influence on PS.