Kerstin Jessica Plessen

Background: Irritability is highly prevalent in adolescents and may be exacerbated by sleep disturbances, with sleep patterns undergoing significant changes during this developmental period. Reciprocally, poor sleep may generate an increase in anger dysregulation. This exploratory study investigates the day‐to‐day associations between sleep and irritability, as well as the moderating effects of maladaptive (i.e., anger rumination) and adaptive (i.e., self‐control) emotion regulation (ER) strategies. Methods: Fifty‐six male adolescents aged 12–18, with diverse sleep and emotional problems, participated in a 9‐day experience sampling method study. Participants also completed self‐report questionnaires assessing irritability, sleep quantity and quality, and maladaptive and adaptive ER strategies. Linear mixed effect models with lagged covariates were used to test associations and moderating effects. Results: At the within‐person level, sleep quality was associated with next‐day irritability ( β std = −0.92, 95% CI [−1.31, −0.53). Higher daily anger rumination ( β std = 0.25, 95% CI [0.17, 0.34]), and daily self‐control ( β std = −0.18, 95% CI [−0.27, −0.10]) were directly associated with higher next‐day irritability. At the between‐person level, lower self‐control was also associated with higher next‐day irritability ( β std = −0.52, 95% CI [−0.77, −0.27]). Interactions between daily sleep quality and between‐person anger rumination ( = 0.18, 95% [0.07, 0.30]), and self‐control ( = 0.75, 95% CI [0.38, 1.12]) were related with irritability. Reciprocally, lower irritability from the day was associated with better sleep quality the following night ( β std = −0.11, 95% CI [−0.20, −0.01]). Conclusion: These preliminary findings suggest that sleep may be related to next‐day irritability in adolescent boys and may vary as a function of anger rumination and self‐control. Additionally, irritability also showed a potential association with subsequent sleep. However, findings should be interpreted cautiously given the small, all‐male adolescent sample. Future studies including larger and more diverse adolescent samples are needed to assess their generalizability and robustness.

Background: Adolescence represents a developmental period marked by heightened vulnerability to suicidal thoughts and behaviors (STBs), which remain a leading cause of death among youth, particularly psychiatric inpatients and after discharge. Contemporary ideation-to-action models conceptualize suicidal crises as dynamic processes driven by proximal psychological factors rather than static risk markers. While recent work has begun to examine these processes as they unfold in daily life, their integration into the clinical course of suicidal distress remains limited. From this perspective, relating short-term microlevel processes of STBs to their broader temporal changes across the transition of adolescents from acute inpatient hospitalization to early ambulatory aftercare constitutes an important area for further investigation. Objective: This protocol describes a multimodal, intensive longitudinal study examining the temporal unfolding of suicidal distress across complementary timescales. The integrative framework aims to identify prototypical trajectories of STBs from inpatient admission through the early postdischarge period. It further seeks to characterize heterogeneity in within-person processes central to ideation-to-action theories and STB-related affect regulation. Finally, the study aims to interrelate these microlevel dynamics of suicidal distress with its longitudinal trajectories at the macrolevel. Within this framework, the study examines how modifiable bioregulatory factors, including sleep and physical activity, as well as clinical process factors such as therapeutic alliance, are dynamically implicated across timescales. Methods: The study plans to recruit 100 adolescents hospitalized at a single site in French-speaking Switzerland. Within 72 hours of admission, participants start a first assessment period of up to 14 days, comprising 4 daily Ecological Momentary Assessment (EMA) surveys and continuous actigraphy recordings. A second assessment period follows participants for the 10 days after discharge and includes 2 daily EMA surveys. In addition, 4 in-person assessment sessions contextualize the intensive longitudinal time series with baseline clinical characteristics, diagnostic status, therapeutic processes, and episodic stressors. Planned analyses will use multilevel and latent class modeling approaches to identify longitudinal patterns of STBs, characterize between-person differences in within-person dynamics, and examine how these patterns relate to contextual factors. Results: Recruitment began on October 31, 2025, and is expected to continue until June 2028. The protocol was developed through the active integration of former patients’ perspectives and clinicians’ lived experience. Feedback from the first 5 participants supported the current implementation of the protocol. Conclusions: By focusing on the link between intraindividual short-term processes and clinical trajectories of STBs, this study will advance our understanding of how STBs and related psychological and behavioral processes interact over time during a critical period of distress. These insights aim to inform targeted, person-centered approaches to acute psychiatric care, offering better support for vulnerable adolescents transitioning from inpatient to outpatient care. International Registered Report Identifier (IRRID): DERR1-10.2196/93016

Sex differences in brain disorders span age at onset, symptom profiles, disease course and treatment response, and may partly reflect underlying differences in cellular metabolism. Indeed, in vivo evidence of sex-related neurometabolic variation remains sparse, with heterogenous and conflicting findings. Using fast high-resolution whole-brain three-dimensional magnetic resonance spectroscopic imaging, we mapped five brain metabolites in three independent cohorts of healthy participants (total n = 114). In a discovery sample of adolescents scanned at 3 Tesla (3T) (n = 61), males showed higher total N-acetylaspartate (tNAA) across widespread gray matter regions. Regional analyses further revealed opposing sex patterns with a complementary higher total creatine (tCr) observed in females, motivating examination of their ratio as an integrative metabolic index. The tNAA/tCr ratio was consistently higher in males in the discovery sample and this finding was replicated across two independent young-adult samples (3T, n = 26; 7T, n = 27), with a widespread gray and white matter distribution. This tNAA/tCr ratio may link neuronal mitochondrial metabolism with cellular energy buffering, positioning it as a potential index of bioenergetic balance relevant for conditions showing both sex differences and altered neurometabolism, notably multiple sclerosis, Alzheimer disease, and psychosis. Together, these findings reveal a reproducible, distributed metabolic sexual dimorphism in the human brain, and underscore the importance of accounting for sex-specific neurometabolic profiles in studies of brain health and disease.

Advances in three-dimensional magnetic resonance spectroscopic imaging (3D-MRSI) allow for the high-resolution mapping of multiple neurometabolites throughout the entire brain in vivo and within clinically compatible time frames. Leveraging this capability, we created a voxel-based pipeline that corrects and spatially normalizes whole-brain maps of total N-acetylaspartate (tNAA), myo-inositol (Ins), choline compounds (Cho), glutamate + glutamine (Glx) and creatine + phosphocreatine (tCr). We examined 2 different 3D-MRSI dataset: first, a clinical sample of adolescents and young adults at risk for psychosis (n = 21) meeting DSM-5 criteria for Attenuated Psychosis Syndrome (APS) or Schizotypal Personality Disorder (SCZT), and age-/sex-matched healthy controls (n = 13); and second, a non-clinical sample of adolescents (n = 61) scanned on a different site. The objective of the study was threefold: first, to assess the reproducibility of 3D-MRSI measures across datasets and scanning sites; second, to validate the feasibility of whole-brain, voxel-based analyses on 3D-MRSI data; and third, to test the sensitivity of this approach. Metabolite distributions showed reproducible regional variation in standard space between the two independent samples and scanning sites (r ranging from 0.82 to 0.99). Relative to controls, at-risk participants exhibited higher tNAA levels in frontal grey matter; the SCZT subgroup additionally displayed widespread cortical and subcortical elevations of Ins levels compared with both APS and controls. Voxel-based analyses of structural (i.e., gray and white matter volumes or densities) and diffusion (i.e., generalized fractional anisotropy) parameters yielded no significant differences between patients and controls. These preliminary findings suggest that high-resolution 3D-MRSI may be sensitive enough to detect subtle neurometabolic alterations at the group level in the early stages of psychotic disorders when structural or diffusion measures show no difference. High-resolution whole-brain metabolic mapping may have the potential to help with early identification of young people at risk for psychosis or other mental disorders.

Background: Adolescence and young adulthood represent critical developmental stages during which mental disorders often emerge, with the potential to impede perceived quality of life. Spirituality (i.e., the search for the sacred) and self-regulation (i.e., intrinsic processes regulating emotions, thoughts, and behaviors) are recognized as protective factors for mental health. However, their dynamic interplay remains largely unexplored, particularly in real-life and in real-time among youths. This study, developed with the help of young partners, addresses this gap by investigating the longitudinal associations between spirituality, self-regulation, and mental health using an ecological momentary assessment (EMA) approach. Methods and analysis: We plan to recruit 120 adolescents and young adults (aged 16–20, expected attrition rate of 20%) from the community to complete a qualitative semi-structured interview assessing their beliefs, spiritual or religious activities, role models, and “meaning in life”. In addition, participants will take part in a multi-wave intensive longitudinal study. Trait-level assessments will be conducted at two time points, three months apart, to capture between-person differences. Additionally, to assess within-person dynamics, participants will complete EMA surveys four times daily over 10 consecutive days in two waves, also three months apart. Measures will include facets of spirituality (e.g., beliefs, meaning, collective consciousness), self-regulation (e.g., self-control, emotional regulation, impulsivity), as well as mental health indicators (emotional and behavioral symptoms) and quality of life. Qualitative data will be analyzed through a thematic analysis method, whereas quantitative associations will be assessed using Linear Mixed Models (LMM) and network analyses. Ethics and dissemination: Ethical approval has been obtained, and data collection begun in May 2025. Findings will be disseminated through open access peer-reviewed journals, conferences on adolescent mental health, and shared with practitioners, educators, and youth organizations. Results will also be made accessible to the general public. This study aims to inform personalized preventive and therapeutic interventions by elucidating real-time mechanisms linking spirituality, self-regulation, and mental health in youths. Strengths and limitations of this study: This study design combines qualitative and quantitative approaches. We use real-time, multi-wave ecological momentary assessment (EMA) to examine spirituality, self-regulation, and mental health in youths. We capture both within- and between-person variations, providing a fine-grained understanding of the temporality and dynamics of these processes. We integrate multiple dimensions of spirituality, self-regulation, and mental health rather than focusing on single constructs. Real-life and real-time assessments reduce recall bias and increase relevance to daily experiences. We invited a panel of youths from the general population to provide feedback during the development phase of the project. The results may not be generalizable to younger adolescents or older adults as the age range is restricted to 16–20 years. Reliance on self-reported data may introduce bias (e.g., social desirability, subjective interpretation).

BACKGROUND Adolescence represents a developmental period marked by heightened vulnerability to suicidal thoughts and behaviors (STBs), which remain a leading cause of death among youth, particularly psychiatric inpatients and after discharge. Contemporary ideation-to-action models conceptualize suicidal crises as dynamic processes driven by proximal psychological factors rather than static risk markers. While recent work has begun to examine these processes as they unfold in daily life, their integration into the clinical course of suicidal distress remains limited. From this perspective, relating short-term microlevel processes of STBs to their broader temporal changes across the transition of adolescents from acute inpatient hospitalization to early ambulatory aftercare constitutes an important area for further investigation. OBJECTIVE This protocol describes a multimodal, intensive longitudinal study examining the temporal unfolding of suicidal distress across complementary timescales. The integrative framework aims to identify prototypical trajectories of STBs from inpatient admission through the early postdischarge period. It further seeks to characterize heterogeneity in within-person processes central to ideation-to-action theories and STB-related affect regulation. Finally, the study aims to interrelate these microlevel dynamics of suicidal distress with its longitudinal trajectories at the macrolevel. Within this framework, the study examines how modifiable bioregulatory factors, including sleep and physical activity, as well as clinical process factors such as therapeutic alliance, are dynamically implicated across timescales. METHODS The study plans to recruit 100 adolescents hospitalized at a single site in French-speaking Switzerland. Within 72 hours of admission, participants start a first assessment period of up to 14 days, comprising 4 daily Ecological Momentary Assessment (EMA) surveys and continuous actigraphy recordings. A second assessment period follows participants for the 10 days after discharge and includes 2 daily EMA surveys. In addition, 4 in-person assessment sessions contextualize the intensive longitudinal time series with baseline clinical characteristics, diagnostic status, therapeutic processes, and episodic stressors. Planned analyses will use multilevel and latent class modeling approaches to identify longitudinal patterns of STBs, characterize between-person differences in within-person dynamics, and examine how these patterns relate to contextual factors. RESULTS Recruitment began on October 31, 2025, and is expected to continue until June 2028. The protocol was developed through the active integration of former patients’ perspectives and clinicians’ lived experience. Feedback from the first 5 participants supported the current implementation of the protocol. CONCLUSIONS By focusing on the link between intraindividual short-term processes and clinical trajectories of STBs, this study will advance our understanding of how STBs and related psychological and behavioral processes interact over time during a critical period of distress. These insights aim to inform targeted, person-centered approaches to acute psychiatric care, offering better support for vulnerable adolescents transitioning from inpatient to outpatient care. CLINICALTRIAL INTERNATIONAL REGISTERED REPORT DERR1-10.2196/93016

Background: Adolescence is marked by increased vulnerability to sleep disturbances and mood disorders. Understanding how day‐to‐day changes in sleep and mood are linked within the same individual is crucial for clarifying sleep's role in emerging internalizing disorders. However, the extent to which an adolescent's fluctuations in sleep predict next‐day mood may differ across individuals. This study examined such differences in person‐specific sleep‐mood dynamics and their links with depression and anxiety symptoms. Methods: A total of 113 Swiss adolescents (57% female, mean age = 15.4 years, SD = 0.97) participated in three 3‐week waves of combined actigraphy, four daily Ecological Momentary Assessments (EMA), and weekly reports of depressive and anxiety symptoms. Bayesian multilevel models estimated person‐specific associations across two mood dimensions (sad‐vs‐happy and anxious‐vs‐calm) combined with sleep duration (SDur), sleep midpoint (SMid), and sleep regularity (SReg; i.e., overlap between each daily cycle and the participant's most typical cycle). Bayesian hypothesis tests examined evidence for differences in person‐specific associations and whether these differences predicted internalizing symptoms. Results: Person‐specific associations involving SDur or SMid showed within‐person effects at the group‐level, but no convincing evidence for individual differences in this dynamic. In contrast, there were clear individual differences in how SReg related to anxious‐vs‐calm mood ( τ ² = 0.47, [0.09; 0.79], BF ₁₀ = 13.2). Adolescents whose calm mood was more strongly tied to a regular sleep–wake cycle reported fewer anxiety symptoms ( b = 3.57, 95%CrI [‐3.67; 9.31], BF ₀₁ = 7.69). Conclusion: Our findings suggest that adolescents whose daytime mood is closely coupled with regular sleep–wake patterns may experience protection against anxiety symptoms. They also show that adolescents differ meaningfully in these sleep–mood associations, challenging conventional group‐level approaches. Future work should extend this idiographic approach to more diverse populations and longer timescales to clarify the role of sleep–mood dynamics in internalizing disorders.

Background: Promoting healthy behaviors including adequate sleep, regular physical activity, balanced diet, and abstinence from substance use, alongside nurturing affective functioning, may crucially support physical and mental well-being in youth. Yet, little is known about how these domains interact dynamically in their daily lives. Objective: This pilot study evaluates the feasibility of prolonged, multiwave ambulatory assessment in school-recruited adolescents as well as in clinical and school-recruited preadolescents. In addition, it will examine the dynamic interplay of different health behavior domains and affective functioning in adolescent samples recruited in schools. Methods: The initial target sample size was 100 youths (ages 9‐17 years) across 2 assessment protocols. Adolescents complete three 3-week waves with 4 daily ecological momentary assessments and parallel actigraphy, and preadolescents follow two 10-day assessment waves. Feasibility aims will be assessed via equivalence tests targeting an a priori level of missing data and dropout at 70% each. Dynamic modeling in adolescent datasets will be addressed by a planned multilevel analysis leveraging idiographic effects as predictors of symptom outcomes, as well as state-of-the-art exploratory frameworks. Results: By July 2025, we enrolled 113 school adolescents and 27 school preadolescents exceeding the a priori target. Recruitment and data collection are still ongoing in the clinical preadolescent group of currently 13 preadolescents. Conclusions: This concise, intensive longitudinal protocol provides the basis for examining the feasibility of long-term intensive longitudinal paradigms in youth and lays a critical foundation for future large-scale studies aimed at unpacking the evolving interplay of health behaviors and emotional well-being.