Josjan Zijlmans

3,4-methylenedioxymethamphetamine (MDMA) is widely described as an “empathogen”, yet empathy is not a unitary process. Here we review MDMA’s social effects by decomposing them into social perception and emotion discrimination, sociability and social reward, affective sharing, cognitive empathy and mentalizing, and prosocial behaviour. Available evidence gathered in humans and other mammals demonstrate that MDMA has distinct effects across these domains, although research coverage remains uneven across domains. We argue that MDMA is best understood not as a global empathy enhancer, but as a domain-specific modulator of social reward, threat perception, positive-valence affective sharing, and interpersonal appraisal. Moving beyond this simplified empathy enhancer concept is essential for understanding both the therapeutic promise and the interpersonal risks of MDMA.

Objective. The COVID-19 pandemic was a major global stressor for children and adolescents, raising concerns about longer-term consequences for mental health and wellbeing. Many studies reported increased mental health problems during and shortly after the pandemic, but less is known about longer-term post-pandemic patterns across domains and informants.Method. We used repeated cross-sectional data from Dutch children and adolescents aged 8-18 years in the Netherlands Twin Register (NTR, N = 39,178, 50% girls) and a representative general-population sample (N = 2,782, 48% girls). Parent- and child-reported mental health problems and wellbeing were assessed using pre-pandemic, pandemic, and post-pandemic data through 2025. Post-pandemic patterns were examined by comparing 2024/2025 outcomes with 2023 and pre-pandemic levels using pre-registered multilevel models.Results. Parent-reported internalizing and externalizing problems in 2024/2025 did not differ from 2023 levels (B = -0.03 to 0.03), but remained higher than pre-pandemic levels (B = 0.28 to 0.31). Child-reported depressive symptoms were lower in 2025 than in 2023 (B =-2.31), anxiety did not differ (B =-0.75), and anger was higher (B =1.13). Compared with pre-pandemic levels, child-reported depression, anxiety, and anger were all higher in 2025 (p <.001). Wellbeing patterns were mixed across informants and samples (B =-1.05 to 0.10).Conclusions. Up to 2025, youth mental health and wellbeing did not show a general return to pre-pandemic levels. Patterns differed across domains and informants, highlighting the importance of continued multi-informant monitoring.

Young adults must learn to navigate increasingly complex social demands. However, youth with co-morbid externalizing and internalizing psychopathology may show slower habituation to socio-emotional cues, indicative of prolonged threat reactivity or socio-affective disengagement, which could contribute to persistent aggression by reducing sensitivity to others’ affiliative and distress cues. In the current study, we test whether interacting levels of internalizing and externalizing problems are associated with amygdala habituation and whether habituation predicted recidivism. For this purpose, ninety-eight multi-problem young adults (18-27y) with a history of antisocial behavior underwent fMRI during an emotional face-matching task presenting fearful, angry, sad, happy and neutral faces. To assess habituation, a well-established habituation index was derived to study how emotional faces were processed. Internalizing and externalizing symptoms were measured with the Adult Self-Report. Recidivism was obtained from Dutch national judicial records (median follow-up 2.5 years post-scan). Amygdala responses showed emotion-dependent habituation, with the strongest habituation for happy faces and relatively weaker habituation for negative and neutral expressions. Moreover, co-occurring internalizing symptoms amplified the association between externalizing symptoms and recidivism. However, amygdala habituation was not associated with externalizing and internalizing symptom levels and neither predicted recidivism nor moderated symptom-recidivism associations. In this high-risk sample, amygdala habituation appears more pronounced for affiliative cues than for negative emotions, but individual differences in habituation did not explain prospective reoffending beyond symptom profiles. Clarifying whether affiliative cues show stronger habituation due to adaptive safety learning or reduced engagement may help refine interventions to enhance sensitivity to prosocial signals and changing social demands.Keywords: habituation, externalizing, internalizing, recidivism, amygdala, fMRI.

Background: As a large‐scale global stressor, the COVID‐19 pandemic has a substantial impact on the mental health of children and adolescents. In this longitudinal study we investigate long‐term trajectories of anxiety of children during and after the pandemic (April 2020–April 2023), and identify associated risk factors. Methods: A total of 514 children from a representative sample of the Dutch general population completed the Patient Reported Outcomes Measurement Information System Anxiety computerized adaptive test at least four of seven bi‐annual assessments (from April 2020 to April 2023). Longitudinal k‐means clustering analyses were conducted to identify distinct anxiety trajectories. The optimal solution was selected based on the Calinski‐Harabasz criterion and interpretability. We assigned participants to their best fitting cluster and compared sociodemographic characteristics between the clusters using T ‐tests and chi‐square tests to identify risk factors. Results: We identified five distinct longitudinal trajectories of anxiety; stable high ( n = 71, 13.8%), stable medium ( n = 109, 21.2%), stable low ( n = 147, 28.6%), recovering ( n = 100, 19.5%) and delayed increase trajectories ( n = 87, 16.9%). The recovering group showed a return to anxiety levels within normal limits over time, while the delayed increase group experienced increased anxiety symptoms after the pandemic. Loss of income from the parents was identified as an important risk factor of belonging to the stable high trajectory (OR range 4.1–8.2, p < 0.001). Conclusion: Children followed distinct anxiety trajectories during and after the COVID‐19 pandemic, showing variability in their long‐term mental health responses. Five trajectories were identified, and parental loss of income emerged as a strong risk factor for less favorable trajectories. These findings show the importance of monitoring mental health over longer periods and especially children that experience additional adversity on top of global stressors might be at risk for lasting mental health problems.

Background: The coronavirus disease 2019 (COVID-19) pandemic has impacted global mental health, with individuals with severe mental illness (SMI) being particularly vulnerable. Research on changes in psychiatric symptoms during this pandemic has yielded inconsistent results, often due to individual heterogeneity and a limited focus on broader outcomes such as psychosocial functioning, societal and personal recovery, and quality of life (QoL). Furthermore, long-term effects remain underexplored. This longitudinal cohort study aimed to assess the COVID-19 pandemic’s impact on mental and psychosocial functioning, QoL, and recovery in individuals with SMI, and to explore individual and treatment characteristics associated with outcome changes. Methods: Two cohorts were included, involving adults (≥18 years) diagnosed with DSM-5 disorders and experiencing long-term impairments. Participants received care between January 1, 2018 and December 31, 2023. Outcomes included the Health of the Nation Outcome Scales, the Manchester Short Assessment of Quality of Life, and the Individual Recovery Outcomes Counter. Changes were analyzed across five pandemic periods using linear mixed models. Results: Improvements in mental and psychosocial functioning, QoL, and recovery were observed over time, regardless of the COVID-19 pandemic period. However, progress was slower during the COVID-19 pandemic compared to pre-pandemic levels. No individual or treatment characteristics were significantly linked to changes in outcomes. Conclusion: The findings suggest that the COVID-19 pandemic had a minimal negative impact on individuals with SMI. This may be due to the marginal negative effects of the pandemic on this population, or the mitigating role of stabilizing factors within the current Dutch care models.

The COVID-19 pandemic negatively affected child and adolescent mental health, but it is unclear which subgroups were affected most. We investigated to what extent severity and type of mental health problems during and after the pandemic were related to preexisting mental disorders in children in care at child and adolescent mental health services. We employed a repeated cross-sectional design involving data collection at seven time points (April 2020 to April 2023) in a total sample of 2,545 children (age 8–18 years). We grouped diagnostic classifications in four categories: Autism, ADHD, Anxious/Depressive disorders, and ‘Other’. Mental health was assessed with parent‐reported data on internalizing and externalizing problems and with self‐reported data from the standardized PROMIS questionnaires ‘Anxiety’, ‘Depressive symptoms’, ‘Sleep‐related impairments’, ‘Anger’, ‘Global health’, and ‘Peer relations’. We tested for main effects between diagnostic categories and for different trajectories over time. We found that mental health outcomes varied substantially between diagnostic categories, with internalizing problems being largest in children with Anxious/Depressive disorders, and externalizing problems being largest in children with Autism and ADHD. However, we found no evidence for differences between diagnostic categories in trajectories in mental health outcomes during and after the COVID-19 pandemic. The results show that during the pandemic mental health outcomes worsened over time in children and adolescents in care, and that this negative effect on mental health did not differ between children with different diagnostic classifications. Regular high-quality monitoring is vital to recognize changing trajectories of youth mental health and to adapt to crisis situations.

Background: The FAIR (Findable, Accessible, Interoperable, Reusable) data principles are a guideline to improve the reusability of data. However, properly implementing these principles is challenging due to a wide range of barriers. Objectives: To further the field of FAIR data, this study aimed to systematically identify barriers regarding implementing the FAIR principles in the area of child and adolescent mental health research, define the most challenging barriers, and provide recommendations for these barriers. Methods: Three sources were used as input to identify barriers: (1) evaluation of the implementation process of the Observational Medical Outcomes Partnership Common Data Model by 3 data managers; (2) interviews with experts on mental health research, reusable health data, and data quality; and (3) a rapid literature review. All barriers were categorized according to type as described previously, the affected FAIR principle, a category to add detail about the origin of the barrier, and whether a barrier was mental health specific. The barriers were assessed and ranked on impact with the data managers using the Delphi method. Results: Thirteen barriers were identified by the data managers, 7 were identified by the experts, and 30 barriers were extracted from the literature. This resulted in 45 unique barriers. The characteristics that were most assigned to the barriers were, respectively, external type (n=32/45; eg, organizational policy preventing the use of required software), tooling category (n=19/45; ie, software and databases), all FAIR principles (n=15/45), and not mental health specific (n=43/45). Consensus on ranking the scores of the barriers was reached after 2 rounds of the Delphi method. The most important recommendations to overcome the barriers are adding a FAIR data steward to the research team, accessible step-by-step guides, and ensuring sustainable funding for the implementation and long-term use of FAIR data. Conclusions: By systematically listing these barriers and providing recommendations, we intend to enhance the awareness of researchers and grant providers that making data FAIR demands specific expertise, available tooling, and proper investments.

Introduction: The positive results of MDMA from Phase 2 and 3 clinical trials in MDMA-assisted therapy (MDMA-AT) for the treatment of post-traumatic stress disorder (PTSD) call for a critical evaluation of its regulatory status within the European mental healthcare system. This is driven by the recent submission of MDMA-AT for FDA approval in the United States. Unless coordinated efforts in the European regulatory landscape start, there may be potential divergences in national regulatory strategies. Gaining insights from researchers and clinicians involved in the application of MDMA-AT may be useful in guiding the discussion of factors involved in its implementation.Method: A comprehensive invitation-only survey was sent to researchers and clinicians involved in MDMA-AT clinical trials and contributors to the scientific literature on MDMA-AT from around the globe. This study aimed to collect opinions on clinical practices, training, and regulation worldwide, examining the global best practices and pitfalls to outline strategies for possible European implementation of MDMA-AT.Results: The survey, which included responses from 68 experts, yielded a range of opinions where a large majority endorsed the need for training and standardization, emphasizing equity and access, stressing impediments in the national approval processes, and reflecting critically on anticipated spill-over effects of MDMA-AT in clinical settings.Conclusion: The experts highlight the need for science-informed policy development, active regulatory involvement, and international cooperation to incorporate MDMA-AT into the European mental healthcare system in general and the treatment of PTSD in particular. The study emphasizes the importance of ongoing research, open professional discourse, and collaborative engagement to facilitate MDMA-AT's ethical and effective implementation.