Neurobiological effects of perceived stress are different between adolescents and middle-aged adults

Epigenome-wide association study of long-term psychosocial stress in older adults

Long-term psychosocial stress is strongly associated with negative physical and mental health outcomes, as well as adverse health behaviours; however, little is known about the role that stress plays on the epigenome. One proposed mechanism by which stress affects DNA methylation is through health behaviours. We conducted an epigenome-wide association study (EWAS) of cumulative psychosocial stress (n = 2,689) from the Health and Retirement Study (mean age = 70.4 years), assessing DNA methylation (Illumina Infinium HumanMethylationEPIC Beadchip) at 789,656 CpG sites. For identified CpG sites, we conducted a formal mediation analysis to examine whether smoking, alcohol use, physical activity, and body mass index (BMI) mediate the relationship between stress and DNA methylation. Nine CpG sites were associated with psychosocial stress (all p < 9E-07; FDR q < 0.10). Additionally, health behaviours and/or BMI mediated 9.4% to 21.8% of the relationship between stress and methylation at eight of the nine CpGs. Several of the identified CpGs were in or near genes associated with cardiometabolic traits, psychosocial disorders, inflammation, and smoking. These findings support our hypothesis that psychosocial stress is associated with DNA methylation across the epigenome. Furthermore, specific health behaviours mediate only a modest percentage of this relationship, providing evidence that other mechanisms may link stress and DNA methylation.

Interaction of perceived social support and childhood maltreatment on limbic responsivity towards negative emotional stimuli in healthy individuals

Childhood maltreatment (CM) is associated with increased limbic activity, while social support is linked to decreased limbic activity towards negative stimuli. Our study aimed to explore the interaction of perceived social support with CM, and their combined impact on limbic activity in negative emotion processing. A total of 130 healthy individuals (HC) underwent a negative emotional face processing paradigm. They were divided into two groups based on the Childhood Trauma Questionnaire: n = 65 HC without CM matched with n = 65 HC with CM. In a region-of-interest approach of the bilateral amygdala-hippocampus-complex (AHC), regression analyses investigating the association of CM and perceived social support with limbic activity and a social support x CM ANCOVA were conducted. CM was associated with increased AHC activity, while perceived social support tended to be associated with decreased AHC activity during negative emotion processing. The ANCOVA showed a significant interaction in bilateral AHC activity (pFWE ≤ 0.024) driven by a negative association between perceived social support and bilateral AHC activity in HC without CM. No significant association was observed in HC with CM. Exploratory analyses using continuous CM scores support this finding. Our results suggest that CM moderates the link between perceived social support and limbic activity, with a protective effect of perceived social support only in HC without CM. The lack of this effect in HC with CM suggests that CM may alter the buffering effect of perceived social support on limbic functioning, highlighting the potential need for preventive interventions targeting social perception of HC with CM.

Family Environmental Risk and Perceived Stress in Adolescent Depressive Symptoms: A Network Analysis

This study, grounded in the Process-Person-Context-Time framework, investigates the complex interplay of family environmental factors and their influence on adolescent depressive symptoms, focusing on the role of 'perceived stress'. Using network analysis, we examined data from 735 junior high students (52.1% female adolescents) from three provinces in China (Jiangsu, Shandong, and Henan), with an average age of 13.81 ± 0.92 years, ranging from 12 to 16 years, exploring the relationships between depressive symptoms, perceived stress, and seven family risk factors. The analysis identified three distinct communities. The incorporation of perceived stress led to its integration into a community that included depressive symptoms, parental restrictive monitoring, and family economic strain. Perceived stress emerged as the strongest predictor of depressive symptoms, surpassing parental restrictive monitoring. Furthermore, it overtook depressive symptoms as the node with the strongest bridging connection within its community. These findings underscore the importance of interventions targeting both family conditions and the internal processing of these stressors by adolescents, especially in challenging family environments, to mitigate the risk of depression and promote resilience.

Perceived Stress From Childhood to Adulthood and Cardiometabolic End Points in Young Adulthood: An 18-Year Prospective Study

BACKGROUND

We investigated how childhood-to-adulthood perceived stress patterns predict adult cardiometabolic risk.

METHODS AND RESULTS

This study included 276 participants from the Southern California Children's Health Study (2003-2014), and a follow-up assessment (2018-2021). Perceived stress (Perceived Stress Scale) was initially reported by participants' parents for themselves during early childhood (mean age, 6.3 years), and later self-reported during adolescence (13.3 years) and young adulthood (23.6 years). Participants were grouped into 4 stress patterns: consistently high, decreasing, increasing, and consistently low. Cardiometabolic risk was assessed in young adulthood by carotid artery intima-media thickness, systolic and diastolic blood pressure, obesity, percent body fat, android/gynoid ratio, and glycated hemoglobin. A cardiometabolic risk score was generated by summing the clinically abnormal markers. Multivariable linear and logistic regression models were used to (1) examine the associations between Perceived Stress Scale at 3 time points and adult cardiometabolic risk, and (2) assess the impact of stress pattern on adult cardiometabolic risk. Findings suggested that in adulthood, higher Perceived Stress Scale score was associated with increased overall cardiometabolic risk (β=0.12 [95% CI, 0.01-0.22]), carotid artery intima-media thickness (β=0.01 [95% CI, 0.0003-0.02]), systolic blood pressure (β=1.27 [95% CI, 0.09-2.45]), and diastolic blood pressure (β=0.94 [95% CI, 0.13-1.75]). Individuals with a consistently high adolescence-to-adulthood stress pattern had greater overall cardiometabolic risk (β=0.31 [95% CI, 0.02-0.60]), android/gynoid ratio (β=0.07 [95% CI, 0.02-0.13]), percent body fat (β=2.59 [95% CI, 0.01-5.17]), and greater odds of obesity (odds ratio, 5.57 [95% CI, 1.62-19.10]) in adulthood, compared with those with a consistently low Perceived Stress Scale score.

CONCLUSIONS

Consistently high perceived stress from adolescence to adulthood may contribute to greater cardiometabolic risk in young adulthood.

The double-edged sword of the hippocampus-ventromedial prefrontal cortex resting-state connectivity in stress susceptibility and resilience: A prospective study

The hippocampus has long been considered a pivotal region implicated in both stress susceptibility and resilience. A wealth of evidence from animal and human studies underscores the significance of hippocampal functional connectivity with the ventromedial prefrontal cortex (vmPFC) in these stress-related processes. However, there remains a scarcity of research that explores and contrasts the roles of hippocampus-vmPFC connectivity in stress susceptibility and resilience when facing a real-life traumatic event from a prospective standpoint. In the present study, we investigated the contributions of undirected and directed connectivity between the hippocampus and vmPFC to stress susceptibility and resilience within the context of the COVID-19 pandemic. Our findings revealed that the left hippocampus-left vmPFC connectivity prior to the pandemic exhibited a negative correlation with both stress susceptibility and resilience. Specifically, individuals with stronger left hippocampus-left vmPFC connectivity reported experiencing fewer stress-related feelings during the outbreak period of the epidemic but displayed lower levels of stress resilience five months later. Our application of spectral dynamic causal modeling unveiled an additional inhibitory connectivity pathway from the left hippocampus to the left vmPFC in the context of stress susceptibility, which was notably absent in stress resilience. Furthermore, we observed a noteworthy positive association between self-inhibition of the vmPFC and stress susceptibility, with this effect proving substantial enough to predict an individual's susceptibility to stress; conversely, these patterns did not manifest in the realm of stress resilience. These findings enrich our comprehension of stress susceptibility and stress resilience and might have implications for innovative approaches to managing stress-related disorders.

Long-term association between neighbourhood socioeconomic deprivation in early childhood and perceived stress in early adulthood: a multilevel cohort study

BACKGROUND

Previous studies have shown that neighbourhood socioeconomic deprivation is related to mental health problems, with chronic stress responses as one possible biopsychological pathway; however, less is known about the possible long-term effects of neighbourhood deprivation throughout the life course. The aim of this study was to examine the association between neighbourhood socioeconomic deprivation in early childhood and perceived stress in early adulthood.

METHODS

Data from the, Danish National Health Survey 2017 in which Cohen's 10-item Perceived Stress Scale was measured (range 0-40) were used to follow a cohort consisting of all survey respondents aged 20-24 years born between 1992 and 1996. The respondents were linked to Danish register data, including data on the parent(s) with whom the respondents lived, to measure family-level socioeconomic characteristics, parental mental health problems and neighbourhood socioeconomic deprivation at age 3 for each respondent. Furthermore, the respondents were linked to georeferenced neighbourhoods. Linear mixed models were used to estimate the association between neighbourhood socioeconomic deprivation at age 3 and perceived stress at age 20-24.

RESULTS

A 1 SD increase in neighbourhood socioeconomic deprivation in early childhood was associated with a 0.59-point increase in perceived stress in early adulthood (95% CI 0.41 to 0.77). The association was attenuated but remained statistically significant after controlling for individual and family characteristics and neighbourhood socioeconomic deprivation in early adulthood (coef 0.26, 95% CI 0.06 to 0.46).

CONCLUSION

The findings suggest that children growing up in more socioeconomically deprived neighbourhoods may be prone to higher levels of perceived stress later in life.

Effects of dorsolateral prefrontal cortex stimulation on network topological attributes in young individuals with high-level perceived stress: A randomized controlled trial

Individuals with high-level perceived stress are at higher risk of developing a psychiatric disorder. While repetitive transcranial magnetic stimulation (rTMS) is effective for improving emotional symptoms, there is little evidence of its effect on perceived stress. This randomized sham-controlled trial investigated the effect of rTMS on ameliorating high-level stress and explored the associated changes in brain network activity. Fifty participants with high-level perceived stress were randomly assigned to either the active or sham rTMS group and received 12 active/sham rTMS sessions over four weeks (three per week). Perceived stress score (PSS), Chinese affective scale (CAS) normal and now statuses, and functional network topology were measured. Our results showed greater improvements in PSS and CAS_Normal scores, and reduced path length in the default mode network after active rTMS. Functional activations of the angular gyrus, posterior insula, and prefrontal cortex were also modulated in the active group. There were significant associations between posterior insula efficiency and PSS scores, and between angular efficiency and CAS_Now scores in the active group. These cumulative findings suggest rTMS as a promising intervention for recovery from high-level perceived stress.

Internet addiction and loneliness among school-going adolescents in Bangladesh in the context of the COVID-19 pandemic: Findings from a cross-sectional study

Internet addiction (IA) by children and adolescents is a concern for parents. The intensity of this problem has increased in the context of COVID-19 pandemic across the world. Here we aimed to evaluate internet usage patterns, addiction to internet use, and mental health among Bangladeshi school-going adolescents during the COVID-19 pandemic. We conducted this cross-sectional study among 502 school-going adolescents. Pre-structured questionnaire was used to collect information related to demographics and the internet usage pattern. We assessed the prevalence of IA and loneliness using the internet addiction test (IAT) scale and UCLA-3 loneliness scale. The prevalence of IA and loneliness among Bangladeshi school-going adolescents were 88.25% and 72.51%, respectively. Individuals with English-medium education, higher classes, high economic status, mobile internet connection, online gaming habits, and living without family showed significantly higher levels of IA. Moreover, a high proportion of loneliness was observed among individuals with high financial conditions, mobile internet connection, and who watch movies on the internet. The present study findings suggest a strong association between demographics, internet usage patterns, IA, and the mental health of adolescents. These results would have practical inferences in clinical psychology, psychotherapy, and related fields. Based on this finding, the healthcare authorities and professionals can develop an inclusive interventional approach for adolescents who suffer from IA and mental health disorders.

Parental psychosocial factors predicting adolescents' psychological adjustment during the surging and remission periods of COVID-19 in China: A longitudinal study

BACKGROUND

Parents play a critical role in adolescents' psychological adjustment, especially in stress response. Few studies have investigated parental impact on adolescents' psychological adjustment in the pandemic. The longitudinal study examined how parental psychosocial factors at the surging period of the pandemic (T1) in China predicted adolescents' anxiety and depression concurrently and at the remission periods three (T2) and six months (T3) later.

METHODS

Middle and high school students and their parents from three schools in Shanghai, China, completed online surveys on March 10, 2020 (T1), June 16, 2020 (T2), and Sep 25, 2020 (T3). Adolescents' anxiety/depression levels were assessed by matching self- and parent-reports at T1, T2, T3, and parents reported their psychological state (emotion and psychopathology), pandemic response (appraisal and coping), and perceived social support (PSS) at T1.

RESULTS

Parental positive/negative emotions, anxiety, depression, control-appraisal, forward- and trauma-focus coping style and PSS were all significantly related to their children's anxiety/depression at T1. All factors, except coping style, predicted adolescents' anxiety/depression at T2 and T3, even after controlling for T1 adjustment levels. Parental positive emotion and depression had the strongest impact on adolescents' adjustment.

LIMITATIONS

Some participants didn't complete the surveys at later time points, and the participants were only recruited in Shanghai.

CONCLUSIONS

The study found that parents' psychosocial factors played a pivotal role on adolescents' psychological adjustment during COVID-19, highlighting the need to provide help to parents who were suffering from potential psychological distress.

Gray matter volume and functional connectivity underlying binge eating in healthy children

PURPOSE

As a maladaptive disordered eating behavior, binge eating (BE) onset has been reported in children as young as eight years old and is linked with a range of negative psychological consequences. However, previous neuroimaging research of BE has mainly focused on adults in clinical conditions, and little is known about the potential neurostructural and neurofunctional bases of BE in healthy children.

METHODS

In this study, we examined these issues in 76 primary school students (mean age = 9.86 years) using voxel-based morphometry and resting-state functional connectivity (rsFC) approaches.

RESULTS

After controlling for age, sex, and total intracranial volume/head motion, we observed that higher levels of BE were correlated with greater gray matter volumes (GMV) in the left fusiform and right insula and weaker rsFC between the right insula and following three regions: right orbital frontal cortex, left cingulate gyrus, and left superior frontal gyrus. No significant associations were observed between BE and regional white matter volume. Significant sex differences were found only in the relationship between BE and GMV in the left fusiform. Furthermore, the GMV- and rsFC-based predictive models (a machine-learning method) achieved significant correlations between the actual and predicted BE values, demonstrating the robustness of our findings.

CONCLUSION

The present study provides novel evidence for the brain structural and functional substrates of children's BE, and further reveals that the weakened communication between core regions associated with negative affectivity, reward responsivity, and executive function is strongly related to dysregulated eating.

LEVEL OF EVIDENCE

Level V, descriptive study.

Prefrontal Cortex Volume Mediates the Relationship Between Lifetime Chronic Stressor Exposure and Cognition in People Living With and Without HIV

OBJECTIVE

Despite considerable research documenting how stress affects brain and neurobehavioral outcomes, few studies have assessed stressor exposure occurring over the entire life span, and no studies have investigated these associations in people living with HIV (PLWH), despite the high stress and disease burden experienced by this population. To address this issue, we examined how cumulative lifetime chronic stressor exposure related to cognition and brain integrity (i.e., gray matter volume) in White and African American PLWH and HIV-uninfected (HIV-) adults.

METHOD

Participants were 91 community-dwelling adults (47.3% PLWH) who completed a comprehensive interview assessing lifetime stressor exposure using the Stress and Adversity Inventory and underwent neuropsychological testing and structural magnetic resonance imaging. Regional brain volumes were derived from T1-weighted images processed through Freesurfer.

RESULTS

As hypothesized, greater lifetime chronic stressor exposure was related to worse global cognition ( b = -0.06, standard error [SE] = 0.03, p = .032), processing speed ( b = -0.04, SE = 0.14, p = .041), and executive functioning ( b = -0.06, SE = 0.02, p = .02), and smaller prefrontal cortex (PFC) volume ( b = -16.20, SE = 5.78, p = .007). HIV status did not moderate any of these associations. Moreover, results from mediation analyses demonstrated that the relationship between lifetime chronic stressor exposure and processing speed was fully mediated by PFC volume.

CONCLUSIONS

These results highlight the critical role of the PFC in the maintenance of processing speed abilities and its vulnerability to cumulative stressor exposure. Specifically, the negative impact of lifetime chronic stressor exposure on cognition-particularly functions reliant on frontal lobe integrity-may be partly driven by smaller volumes in the PFC.

Association of amygdala size with stress perception: Findings of a transversal study across the lifespan

Daily routines are getting increasingly stressful. Interestingly, associations between stress perception and amygdala volume, a brain region implicated in emotional behaviour, have been observed in both younger and older adults. Life stress, on the other hand, has become pervasive and is no longer restricted to a specific age group or life stage. As a result, it is vital to consider stress as a continuum across the lifespan. In this study, we investigated the relationship between perceived stress and amygdala size in 272 healthy participants with a broad age range. Participants were submitted to a structural magnetic resonance imaging (MRI) to extract amygdala volume, and the Perceived Stress Scale (PSS) scores were used as the independent variable in volumetric regressions. We found that perceived stress is positively associated with the right amygdala volume throughout life.

Adverse childhood experiences and perceived stress in early adulthood in the context of disadvantage

BACKGROUND

Adverse childhood experiences (ACEs) may sensitize individuals to view situations in adulthood as more stressful, which may contribute to poor health outcomes. In populations facing disadvantage, ACEs may lead to the accumulation of stressors (stress proliferation or mediation hypothesis) throughout the life course. ACEs could also heighten perceived stress later in life due to its enduring impact (stress sensitization or effect modification hypothesis).

OBJECTIVE

We examine the associations between ACEs and perceived stress in early adulthood, considering concurrent life stressors, in a longitudinal cohort of Puerto Rican youth exposed to a high degree of disadvantage.

PARTICIPANTS AND SETTING

A community-based sample of 1626 Puerto Rican children living in disadvantaged contexts was followed longitudinally in the Boricua Youth Study from 2000 to 2017.

METHODS

ACEs were measured prospectively during childhood (<18 yrs), and life stressors and past year perceived stress were measured in early adulthood (EA; mean age = 23.4, sd 2.22). Causal mediation analysis tested ACEs' effects on EA perceived stress indirectly through life stressors including potential effect modification.

RESULTS

ACEs influenced perceived stress in EA (standardized total effect = 0.13, p < .001) with 35% mediated by increased exposure to life stressors in EA due to ACEs. There was no evidence of increased sensitization to EA life stressors among those with higher ACEs exposure.

CONCLUSIONS

ACEs contribute to perceived stress in EA, albeit with small effect, partially through accumulating effects of ongoing stressors, supporting the stress proliferation hypothesis. Policies aimed at reducing exposure to adversity from childhood to EA are needed to reduce the experience of ACEs and negative sequelae.

Higher Peripheral Inflammation Is Associated With Lower Orbitofrontal Gamma Power in Chronic Tinnitus

Chronic tinnitus, the continuous perception of a phantom sound, is a highly prevalent audiological symptom, for which the underlying pathology has not yet been fully understood. It is associated with neurophysiological alterations in the central nervous system and chronic stress, which can be related with a disinhibition of the inflammatory system. We here investigated the association between resting-state oscillatory activity assessed with Magnetoencephalography (MEG), and peripheral inflammation assessed by C-reactive protein (CRP) in a group of patients with chronic tinnitus (N = 21, nine males, mean age: 40.6 ± 14.6 years). Additionally, CRP was assessed in an age- and sex-matched healthy control group (N = 21, nine males, mean age: 40.9 ± 15.2 years). No MEG data was available for the control group. We found a significant negative correlation between CRP and gamma power in the orbitofrontal cortex in tinnitus patients (p < 0.001), pointing to a deactivation of the orbitofrontal cortex when CRP was high. No significant clusters were found for other frequency bands. Moreover, CRP levels were significantly higher in the tinnitus group than in the healthy controls (p = 0.045). Our results can be interpreted based on findings from previous studies having disclosed the orbitofrontal cortex as part of the tinnitus distress network. We suggest that higher CRP levels and the associated deactivation of the orbitofrontal cortex in chronic tinnitus patients is maintaining the tinnitus percept through disinhibition of the auditory cortex and attentional or emotional top-down processes. Although the direction of the association (i.e., causation) between CRP levels and orbitofrontal gamma power in chronic tinnitus is not yet known, inflammation reducing interventions are promising candidates when developing treatments for tinnitus patients. Overall, our study highlights the importance of considering immune-brain communication in tinnitus research.

Artificial neural network application for identifying risk of depression in high school students: a cross-sectional study

BACKGROUND

Identifying important factors contributing to depression is necessary for interrupting risk pathways to minimize adolescent depression. The study aimed to assess the prevalence of depression in high school students and develop a model for identifying risk of depression among adolescents.

METHODS

Cross-sectional study was conducted. A total of 1190 adolescents from two high schools in eastern China participated in the study. Artificial neurol network (ANN) was used to establish the identification model.

RESULTS

The prevalence of depression was 29.9% among the students. The model showed the top five protective and risk factors including perceived stress, life events, optimism, self-compassion and resilience. ANN model accuracy was 81.06%, with sensitivity 65.3%, specificity 88.4%, and area under the receiver operating characteristic (ROC) curves 0.846 in testing dataset.

CONCLUSION

The ANN showed the good performance in identifying risk of depression. Promoting the protective factors and reducing the level of risk factors facilitate preventing and relieving depression.

Effects of Training with Different Modes of Strength Intervention on Psychosocial Disorders in Adolescents: A Systematic Review and Meta-Analysis

Physical exercise has a positive impact on anxiety and depression. However, the evidence that associates strength training with a decrease in adolescents' psychosocial disorders is scarce. Consequently, the objective was to analyze the effects of training with different modes of strength intervention on anxiety, stress, and depression in adolescents. The search was designed according to PRISMA^®. We searched WoS, Scopus, SPORTDiscus, PubMed, and MEDLINE (2010-2020). Methodological quality and risk of bias were assessed with the Cochrane Collaboration. The analysis was carried out with a standardized mean difference (SMD) pooled using the Hedges g test (95% CI). The Main Outcome Measures were: anxiety, stress, and depression in adolescents post strength training. Nine studies were included in the systematic review and seven in the meta-analysis. These studies showed a large and significant effect of strength training on anxiety (SMD = -1.75; CI = 95%: -3.03, -0.48; p = 0.007) and depression (SMD = -1.61; CI = 95%: -2.54, -0.67, p = 0.0007). In conclusion, training with different modes of strength intervention have shown control over anxiety and depression in adolescents. However, conventional strength training seems to have better results than other modes of strength intervention.

Commercial Off-The-Shelf Video Games for Reducing Stress and Anxiety: Systematic Review

BACKGROUND

Using commercial off-the-shelf video games rather than custom-made computer games could have several advantages for reducing stress and anxiety, including their low cost, advanced graphics, and the possibility to reach millions of individuals worldwide. However, it is important to emphasize that not all commercial video games are equal, and their effects strongly depend on specific characteristics of the games.

OBJECTIVE

The aim of this systematic review was to describe the literature on the use of commercial off-the-shelf video games for diminishing stress and anxiety, examining the research outcomes along with critical variables related to computer game characteristics (ie, genre, platform, time of play).

METHODS

A systematic search of the literature was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. The search databases were PsycINFO, Web of Science, Medline, IEEExplore, and the Cochrane Library. The search string was: [("video game*") OR ("computer game*")] AND [("stress") OR ("anxiety") OR ("relaxation")] AND [("study") OR ("trial") OR ("training")].

RESULTS

A total of 28 studies met the inclusion criteria for the publication period 2006-2021. The findings demonstrate the benefit of commercial off-the-shelf video games for reducing stress in children, adults, and older adults. The majority of the retrieved studies recruited young adults, and fewer studies have involved children, middle-aged adults, and older adults. In addition to exergames and casual video games, other genres of commercial off-the-shelf games helped to reduce stress and anxiety.

CONCLUSIONS

Efficacy in reducing stress and anxiety has been demonstrated not only for exergames and casual video games but also for other genres such as action games, action-adventure games, and augmented reality games. Various gaming platforms, including consoles, PCs, smartphones, mobile consoles, and virtual reality systems, have been used with positive results. Finally, even single and short sessions of play had benefits in reducing stress and anxiety.

TRIAL REGISTRATION

International Platform of Registered Systematic Review and Meta-analysis Protocols INPLASY202130081; https://inplasy.com/?s=INPLASY202130081.

Amygdala size varies with stress perception

Stress is inevitably linked to life. It has many and complex facets. Notably, perception of stressful stimuli is an important factor when mounting stress responses and measuring its impact. Indeed, moved by the increasing number of stress-triggered pathologies, several groups drew on advanced neuroimaging techniques to explore stress effects on the brain. From that, several regions and circuits have been linked to stress, and a comprehensive integration of the distinct findings applied to common individuals is being pursued, but with conflicting results. Herein, we performed a volumetric regression analysis using participants’ perceived stress as a variable of interest. Data shows that increased levels of perceived stress positively associate with the right amygdala and anterior hippocampal volumes.

•

Discrepant stress effects on morphology are reported in the literature.

•

Stress definition and analysis software are the main causes of conflicting findings.

•

Psychological measures and multi-technique analysis are highly recommended.

•

We found that perceived stress positively associates with right amygdala volumes.

Implications of COVID-19 and Lockdown on Internet Addiction Among Adolescents: Data From a Developing Country

Introduction: Physical distancing policy during coronavirus disease 2019 (COVID-19) pandemic requires adolescents to spend most of their time at home, thus increasing Internet use duration. Limited social interaction with their peers may lead to loneliness and an increased risk of mental health among adolescents. This study aimed to assess the prevalence of Internet addiction (IA) among adolescents and analyze the influence of psychosocial factors toward the heightened risk of IA during the COVID-19 pandemic. Methods: An online survey comprising sociodemographic questionnaire, Internet Addiction Diagnostic Questionnaire (KDAI), Strengths and Difficulties Questionnaire (SDQ), and Pittsburgh Sleep Quality Index (PSQI) was distributed. Overall, a total of 2,932 adolescents (mean age, 17.38 ± 2.24 years old; female, 78.7%), originating from 33 of 34 provinces in Indonesia, completed the survey. Results: The point prevalence of IA among Indonesian adolescents during the COVID-19 outbreak was 19.3%. Increased Internet use duration, internalization, externalization, low prosocial behavior, and sleep disturbances were found as risk factors of IA, either directly or as mediating variables. Physical distancing, large-scale social restriction (PSBB), and health status were not correlated to IA. Discussion: Physical distancing was not established as a risk of IA. This could be due to other psychological factors such as internalization, externalization, prosocial, and sleep problems that had correlations to IA occurrence among adolescents in the COVID-19 pandemic. Sleep impairment might have resulted from the emotional and behavioral issues and directly contributed to IA development. Conclusion: The present study found the prevalence of IA among Indonesian adolescents to be higher than the adult during the COVID-19 pandemic. Several psychological measures were indicated to increase the risk of IA, while physical distancing did not elevate the risk. Thus, remote schooling is preferable in Indonesia along with proper parental supervision to minimize Internet use for entertainment purposes.

Parsing inter- and intra-individual variability in key nervous system mechanisms of stress responsivity and across functional domains

Exposure to stressful events is omnipresent in modern human life, yet people show considerable heterogeneity in the impact of stress exposure(s) on their functionality and overall health. Encounter with stressor(s) is counteracted by an intricate repertoire of nervous-system responses. This narrative review starts with a brief summary of the vast evidence that supports heart rate variability, cortisol secretion, and large-scale cortical network interactions as kay physiological, endocrinological, and neural mechanisms of stress responsivity, respectively. The second section highlights potential sources for inter-individual variability in these mechanisms, by focusing on biological, environmental, social, habitual, and psychological factors that may influence stress responsivity patterns and thus contribute to heterogeneity in the impact of stress exposure on functionality and health. The third section introduces intra-individually variability in stress responsivity across functional domains as a novel putative source for heterogeneity in the impact of stress exposure. Challenges and future directions are further discussed. Parsing inter- and intra-individual variability in nervous-system mechanisms of stress responsivity and across functional domains is critical towards potential clinical translation.