European Neuropsychopharmacology

Anxiety and maladaptive fear remain difficult to treat, and despite initial promising findings, evidence regarding the anxiolytic and translational potential of oxytocin (OT) remains inconsistent. In a preregistered, randomized, double-blind, placebo-controlled, parallel-group pharmaco-fMRI study in 67 healthy men, we tested whether intranasal OT reduces post-exposure subjective fear during prolonged naturalistic viewing a horror movie comprising independently defined low-, medium-, and high-fear segments. OT reduced subjective fear following naturalistic threat exposure after accounting for pre-exposure baseline ratings. Neuroimaging analyses revealed that OT attenuated recruitment of the dorsolateral prefrontal cortex particularly during higher fear, and enhanced coupling of this region with the bilateral amygdala. At the large-scale network level, OT increased communication between frontoparietal/default-mode control networks and subcortical/limbic networks during high fear indicating more integrative fear regulation. A whole-brain fear neuromarker (CAFE) further confirmed intensity-dependent OT effects. Together, these findings indicate that OT modulates post-exposure fear experience and fear-related neural dynamics in ecologically valid contexts.

Background: Reduced concentrations of the neuropeptide oxytocin can occur in disorders with social dysfunction, notably autism. However, the role of peripheral endogenous oxytocin concentrations and increased ones following exogenous administration in modulating key social behaviors in humans is still unclear. Here we investigated effects of targeting peripheral oxytocin receptors through oromucosal administration of oxytocin and an oxytocin receptor antagonist (atosiban) on social attention. Methods: We carried out a pre-registered, randomized, double-blind, placebo-controlled experiment with 250 adult male subjects in five treatment groups (placebo + placebo, placebo + 24 IU OT, placebo + 48 IU OT, atosiban + placebo, and atosiban + 24 IU OT), each receiving two oromucosal (lingual) administrations separated by 15 minutes. Following treatment, subjects performed an autism-sensitive dynamic social versus geometric pattern eye-tracking paradigm. Pre- and post-treatment blood samples were collected for oxytocin measurement. Results: Results showed that 48IU but not 24IU oxytocin significantly increased preferential viewing of social stimuli relative to placebo, and effects were associated with, and mediated by, increased oxytocin concentrations and negatively correlated with subjects autism quotient scores. On the other hand, atosiban reduced preference for social stimuli relative to placebo even after subsequent administration of 24IU oxytocin. Conclusions: Our findings suggest that both exogenous and endogenous oxytocin can act via peripheral receptors to enhance interest in social relative to non-social stimuli, possibly influencing the brain via acting on G[q]-coupled receptors in the vagal system. This further supports the therapeutic potential of oxytocin for social dysfunction.

Although non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has demonstrated a therapeutic-relevant potential by enhancing mood recovery and fear extinction, its influence on neural dynamics during naturalistic, sustained fear processing remains unclear. In this study, we employed a randomized, sham-controlled, parallel-group design involving 63 participants (taVNS: n = 33; sham: n = 30) who provided continuous subjective fear ratings (1170 timepoints) while watching a 10-minute fear-inducing video, with simultaneous fNIRS recordings. We employed: (1) a convolutional neural network (CNN) to decode fear ratings from frontal activations, (2) validation of stimulus-evoked activity comparing fNIRS with fMRI signal, (3) dynamic conditional correlation analysis to assess taVNS-induced connectivity changes, and (4) moderation analysis to examine anxiety state effects. Behaviorally, taVNS significantly attenuated fear responses during four threat phases by content analysis: T1 (ghost appearance), T2 (escape sequence), T3 (sudden threat emergence) and T4 (suicide scene). Neurally, taVNS suppressed medial prefrontal cortex (mPFC) activation during escape (T2) and disrupted the typical fear coupling between fear experience and brain activity. Furthermore, taVNS enhanced intra-mPFC functional connectivity, suggesting a potential neural basis for modulating subjective threat appraisal. Additionally, state anxiety significantly moderated brain-behavior relationships. These findings demonstrate that taVNS attenuates fear responses through modulation of mPFC engagement and strengthening frontal network integration. Our results highlight taVNS as a promising neuromodulatory intervention for fear-related disorders (e.g., anxiety disorder), particularly as an early adjunct to exposure-based therapies, warranting further clinical validation.

Anhedonia and motivational impairment are central features of major depressive disorder, yet the neural processes linking reward information to sustained goal-directed behaviour remain insufficiently understood. Using functional magnetic resonance imaging, we examined representations of reward levels during sustained effort expenditure (a construct in the RDoc framework) as a distinct component of reward processing in depressive patients under escitalopram treatment. Twenty-eight unmedicated patients with a current depressive episode and forty-three healthy control participants underwent fMRI scanning at two time points three weeks apart; patients started escitalopram immediately after the first measurement. Across participants, sustained effort expenditure engaged midbrain reward circuitry (ventral tegmental area, VTA), even in the absence of immediate reinforcement. A targeted analysis also revealed changes in activity of the dorsal raphe nucleus (DRN) in patients. Increases in VTA activity were associated with improvements in clinician-rated depressive symptoms, whereas self-reported anhedonia remained unchanged. By isolating neural mechanisms supporting sustained goal-directed behaviour, the study identifies novel and clinically relevant imaging phenotypes of reward processing and a potential pathway of escitalopram treatment in depression.

Negative emotional bias, including reduced processing of positive information and negative interpretation of ambiguous stimuli, is a core feature of depression. Esketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist with rapid antidepressant effects in treatment-resistant depression (TRD), reduces depressive symptoms, but its effects on distinct components of emotional processing remain unclear. Fifty-three patients with TRD and 53 healthy controls performed an Emotional Facial Expression Morphing task. Patients were assessed at baseline, 24 hours after the first esketamine administration, and after 4 weeks of treatment. Statistical models examined detection thresholds for happy and sad faces, negative categorisation of neutral faces, and signal detection indices separating emotion-neutral discrimination sensitivity (d') from response criterion (c), indexing the evidence required to report the presence of an emotion. At baseline, patients required greater happy-face intensity for emotion detection and were more likely to categorise detected neutral faces as negative. They also showed a more conservative response criterion without group difference in discrimination sensitivity. Responders showed an early increase in d'; and, by week 4, less negative categorisation of neutral faces than non-responders. A lower baseline response criterion was associated with responder status and, in secondary continuous analyses, with greater subsequent MADRS improvement. These findings indicate that TRD involves abnormalities across detection-related, valence-related, and decisional aspects of facial-emotion processing that are differently associated with esketamine response: baseline response criterion emerged as a candidate prognostic marker, whereas negative categorisation of neutral faces tracked clinical response. Assessing these domains may inform clinical evaluation, pending independent replication.

Pharmacological treatments targeting core autistic features remain limited. In neurotypical adults, cannabidiol (CBD) alters mismatch negativity (MMN), an electrophysiological marker of automatic auditory deviance detection that has been associated with autistic traits. The effects of CBD on MMN, as measured using electroencephalography (EEG), in autistic children remain unknown. This secondary analysis of a pilot randomised, double-blind, placebo-controlled crossover trial examined the effects of 12 weeks of oral CBD oil on MMN during a duration-deviant auditory oddball task. We hypothesised that CBD would produce more negative MMN amplitudes and shorter peak latencies relative to placebo. Nineteen autistic children (6-12 years, 8 female) received CBD (dose) and placebo in randomised order, separated by an 8-week washout. Age-adjusted linear mixed-effects models tested Time (baseline, follow-up) x Treatment (CBD, placebo) effects on mean MMN amplitude and peak latency separately at Fz and FCz. Exploratory Spearman correlations examined baseline associations between MMN and Developmental Behaviour Checklist-2 (DBC-2) Social Relating scores. At FCz, latency decreased following CBD but increased following placebo but did not survive FDR correction (p = .029, pFDR = .058) and no other interactions were significant. Higher baseline DBC-2 Social Relating scores were associated with more negative MMN amplitude at FCz (rho = -.58, pFDR = .028) and Fz (rho = -.59, pFDR = .028). These findings provide tentative evidence that CBD may modulate MMN latency in autistic children. Larger trials should clarify CBDs effects on MMN and further examine the association between MMN amplitude and social-relating difficulties.

Background: Pavlovian-to-instrumental transfer (PIT) describes how conditioned cues shape instrumentally learned behavior and has been linked to cue-driven alcohol seeking and relapse in alcohol use disorder (AUD). Acute psychosocial stress is an established relapse risk factor that may amplify cue-driven motivational control. Whether acute stress modulates PIT behaviorally and neurally, and whether this differs in AUD, remains unclear. Methods: Within the TRR265 study, 109 participants (62 AUD, 46 controls (CON)) completed a within-subject, randomized, two-day PIT paradigm under Trier Social Stress Test and placebo conditions, with repeated salivary cortisol sampling across sessions. A subsample (n = 62; 34 AUD, 28 CON) underwent fMRI during the transfer phase. Results: A robust PIT effect emerged across groups, and acute stress significantly enhanced cue-driven response vigor (p = .034), with no AUD-specific behavioral effect. Exploratorily, cortisol responders showed stronger stress-related PIT enhancement than non-responders (p = .022). Neurally, PIT engaged the right amygdala during placebo. Acute stress induced less downregulation of PIT-related left amygdala activity in AUD than in CON (pFWE = .019), with no group difference during placebo. Conclusions: Acute psychosocial stress potentiated the motivational influence of non-drug-related conditioned cues on behavior irrespective of AUD status, identifying PIT as a candidate mechanism through which stress may promote alcohol-seeking behavior. Despite comparable behavioral effects, AUD was associated with blunted stress-induced downregulation of PIT-related amygdala activity, suggesting altered neural regulation of cue-driven processing whose relevance for future alcohol consumption and clinical outcome remains to be established.

Importance: Obsessive-Compulsive Disorder (OCD) has a 2% global prevalence, but only about 50% of patients respond to conventional treatment, underscoring the need for additional effective interventions. Objective: To assess the feasibility, safety, and preliminary evidence for efficacy of repeated psilocybin administration in OCD patients who had previously attempted psychotherapy or pharmacotherapy. Design: Waitlist-controlled open label randomized clinical trial. Setting: Data were collected at the Johns Hopkins University School of Medicine. Participants: Data were analyzed from 30 participants (total randomized N=37, by age, sex and OCD severity) with a failed previous attempt at either pharmacotherapy or evidence-based psychotherapies such as exposure response prevention (ERP). Intervention: Participants received two psilocybin doses over two weeks (20 mg followed by 30 mg, if well-tolerated) under supportive conditions. The immediate-treatment arm received the drug within a month following enrollment, and the waitlist-control arm received identical support and dosing after an 8-week waiting period. Main Outcomes: Clinician-administered Y-BOCS scores was collected one week post each drug administration and one month post session 2. Self-assessed reports were collected for acute subjective effects (Mystical Experience Questionnaire (MEQ), Challenging Experience Questionnaire (CEQ), and 11-Dimensional Altered States of Consciousness (11D-ASC)), State-Trait Anxiety Inventory (STAI), Beck Depression Inventory-II (BDI-II), and Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q). Results: A total of 37 participants were enrolled in the study (age[SD] years:38.4[11.6] years; 21 [56.75%] female), with 30 [81.08%] completing the 1-month follow-up. We show that two successive doses of psilocybin over two weeks were well-tolerated, leading to improvements in OCD symptoms. Compared with the waitlist group (N=14), the immediate-treatment group (N=16) showed a greater reduction in the Y-BOCS scores (F(2,56)=16.17, p<0.001). After crossover, this improvement persisted one month after the second psilocybin dose for both groups (F(3,84)=29.91, p<0.001). Reductions in Y-BOCS score post sessions were correlated with several acute subjective effects measures, including total scores on MEQ, and individual factors on CEQ and 11D-ASC. Conclusions and Relevance: Repeated psilocybin administration is tolerable and potentially efficacious in reducing OCD symptoms. These results support further investigation of multidose psilocybin protocols as a viable therapeutic approach. Trial Registration: ClinicalTrials.gov Identifier NCT05546658

Major depressive disorder (MDD) and post-traumatic stress disorder (PTSD) are prevalent, chronic, and disabling mental health conditions which are difficult to treat. Ketamine has demonstrated effect for improving depression and PTSD symptoms independently but reports often overlook focused comorbid improvement of these symptoms within individuals. To address this, we assessed blood-based biomarker and psychological changes following low-dose oral ketamine treatment for adults with MDD alone (n=14) and comorbid MDD+PTSD (n=21). Before treatment, the MDD clinical group presented with more severe depression, lower serotonin levels and higher kynurenine levels than the MDD+PTSD group. Post-treatment there were no detectable differences in the biological response between clinical groups, with combined analysis revealing common decreases in circulating brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF-A). Additionally, post-treatment, both clinical groups showed improvements in anxiety, stress, social functioning, suicidal ideation, and general well-being measures, as well as individual improvements in depression scores and PTSD symptoms in the MDD- and PTSD-containing groups, respectively. Collectively, this study presents additional evidence that low-dose oral ketamine treatment can be effective for MDD and MDD+PTSD, individually and comorbidly, and that both MDD and PTSD clinical groups responded in the same biological manner.

Background: Social difficulties in alcohol use disorder (AUD) have been linked to alterations in social cognition, including increased egocentric bias. Psychedelics such as psilocybin have been proposed to modulate self-related processing, but their effects on specific socio-cognitive mechanisms remain unclear. Methods: In this randomized controlled pilot study, recently detoxified individuals with AUD with persistent depressive symptoms completed a visual perspective-taking task before and after a psilocybin session (25 mg dose vs active placebo 1 mg psilocybin). Results: The 25 mg psilocybin group showed a significant reduction in egocentric bias and egocentric superiority on reaction times, with no effect on altercentric bias nor on accuracy. Between-group comparisons confirmed greater reductions in the high-dose relative to the low-dose group. The high-dose group reported more intense subjective psychedelic experiences, and greater subjective intensity was associated with lower egocentric superiority in accuracy. Conclusions: These findings provide preliminary evidence that psilocybin may selectively reduce egocentric interference in individuals with AUD, suggesting a decrease in egocentricity rather than enhanced sensitivity to others. Although replication in larger samples is needed, reduced egocentricity may represent one mechanism through which psilocybin influences social cognition in AUD. Clinical trial registration: ClinicalTrials.gov, https://clinicaltrials.gov/study/NCT06235411, NCT06235411.

Music is a central component of psychedelic settings, yet little experimental work has examined how psilocybin and musical composition influence music-evoked emotional responses in healthy volunteers. This exploratory, double-blind, placebo-controlled study assessed these effects during the plateau phase of psilocybin and the corresponding time window in placebo sessions following oral administration of psilocybin (0.26 mg/kg) or placebo. The study consisted of two parts. In Part 1 (n = 19), a pilot stage, the first half of participants rated music-induced affective valence for eight compositions representing different genres/subgenres (Rock/Punk, Metal/Industrial Metal, Metal/Industrial Metal, Classical/Baroque, Electronic/Dub, Folk/Nordic Folk, Electronic/Techno, Electronic/Trance, Electronic/Psytrance) using a visual analogue scale (VAS). Based on Part 1, the classical composition with the highest overall affective valence and the psytrance composition with the largest psilocybin-placebo contrast (i.e., the composition most responsive to psilocybin) were selected for Part 2 (n = 17), in which the second half of participants assessed emotional responses to music using the Geneva Emotional Music Scale (GEMS-9). Psilocybin increased wonder, transcendence, and joyful activation across both contrasting compositions. Relative to each other, the classical composition elicited greater peacefulness, tenderness, and nostalgia, whereas the psytrance composition elicited greater tension across both psilocybin and placebo conditions. A composition x condition interaction was observed for sadness: under psilocybin, sadness increased during the classical composition and decreased during the psytrance composition. These findings suggest that psilocybin and contrasting musical compositions independently influence different aspects of music-evoked emotional responses, with limited interaction effects, and point to potential implications for protocol design and music selection in psychedelic settings.

Home-based 2 mA transcranial direct current stimulation (tDCS) was recently approved by the US Food and Drug Administration for depression, but tDCS amplitude has been limited largely by skin tolerance, and higher-intensity, accelerated dosing may be more efficacious or faster-acting. Using a novel high-capacity tDCS (HC-tDCS) stimulator and hydrogel electrodes, we evaluated the safety, tolerability and feasibility of accelerated HC-tDCS (20-minute bifrontal 6 mA sessions, twice daily for five days) in 20 patients with major depressive disorder. A Safety Review Committee reviewed data from the first three participants, who completed a within-day escalation to 6 mA, before the remaining 17 were enrolled. Retention and adherence were 100% (203 of 203 sessions), and 19/20 tolerated the full 6 mA amplitude without dose reduction. There were no serious adverse events. The most common symptoms were fatigue (49% of sessions), burning (46%) and tingling (43%) at the electrode, and difficulty concentrating (40%). Electrode-site erythema occurred in all participants, with no severe reaction or skin breakdown. At 1 week, 7 of 20 reported a residual skin change, mostly peeling or redness, none painful; at 1 month, hyperpigmentation at the electrode site persisted in 2 participants, both Black. At the end of the five-day course, PHQ-9 scores decreased from 15.8 to 7.2 (Hedges g = 1.62); 50% of participants responded, 45% remitted, and improvement was maintained at 1-month follow-up. Accelerated HC-tDCS was feasible, well tolerated, and warrants a sham-controlled trial.

Social connection is fundamental to human wellbeing. Serotonergic psychedelics such as lysergic acid diethylamide (LSD) acutely heighten subjective connectedness, yet their effects on real-time social connection remain poorly understood. Using EEG hyperscanning in a randomized, double-blind, placebo-controlled crossover study, we recorded neural activity simultaneously from both members of healthy romantic couples (N=25) who received LSD (50 g) or placebo together, across resting and interactive states. LSD increased subjective connectedness, including feelings of love, closeness, trust, and being "in sync," while reducing loneliness, compared to placebo. This affiliative shift dissociated from the drugs pharmacokinetic time-course, remaining elevated as subjective intensity and plasma concentration declined. In parallel, LSD increased inter-brain synchrony during shared rest, carried specifically by theta-band amplitude-envelope coupling. Importantly, this effect survived two complementary controls. First, it exceeded coupling between unrelated individuals and second the effects depended on contemporaneous neural alignment rather than shared drug-induced dynamics. Exploratory analyses showed that romantic partners with greater resting synchrony reported greater feelings of connectedness. These findings provide the first evidence that a psychedelic enhances brain-to-brain coupling between people, linking a pharmacologically induced state of felt connection to a measurable signature shared across interacting brains.

Psychiatric symptoms are heterogeneous and change over time, yet clinical assessment relies largely on discrete subjective symptom assessments. We examined whether affective reactivity and autonomic dynamics relate to current clinical state and subsequent symptom change in a transdiagnostic psychiatric sample. Patients were assessed at baseline using an adaptive reward-based mood modulation task (n = 100) and heart rate variability recording (n = 57), with longitudinal clinical data available approximately 4 weeks later (n=34). Patients showed reduced positive affective reactivity and altered linear and nonlinear HRV. Positive affective reactivity was primarily associated with concurrent affective symptoms, whereas LF/HF ratio, Lyapunov exponent and Approximate Entropy were prospectively associated with subsequent symptom improvement. Integrating these HRV features into a multidimensional index yielded a stronger association with symptom change beyond baseline cross-sectional symptom severity, suggesting that this index may provide relevant information about clinical trajectories during treatment.

Background: Substance use is common among individuals with depression. Transcranial magnetic stimulation (TMS) is an effective treatment for depression, but current clinical guidelines have discouraged TMS treatment for individuals with depression and co-occurring substance use given concerns for limited efficacy. However, limited data exists on whether substance use affects response to TMS. Methods: Using electronic health record data from patients who received a standard course of TMS for major depressive disorder at an academic medical center, we investigated associations between substance use frequency and response to TMS, defined as change in Patient Health Questionnaire-9 (PHQ-9) scores. Substance use frequency was extracted for alcohol, cannabis, nicotine, stimulants, benzodiazepines, opioids, inhalants, psychedelics, and other drugs. We performed ANCOVA and multiple regression analyses to predict change in PHQ-9 score based on substance use frequency, controlling for pre-TMS PHQ-9 score, age, sex, and number of TMS sessions received. Results: We extracted data from 219 TMS courses. Alcohol was the substance used most commonly (34.2%), followed by prescription benzodiazepines (28.3%), and prescription stimulants (21.0%). Across all substance categories, substance use was not associated with change in PHQ-9 score (all p > 0.05, Cohens d=0.00 to 0.30). In multiple regression models to compare individual levels of substance use frequency (e.g., daily use vs. no use), level of substance use was not associated with change in PHQ-9 score (all p > 0.05). The range of plausible effects of substance use frequency on PHQ-9 change was generally below the minimal clinically important difference for PHQ-9, suggesting substance use was unlikely to have a meaningful clinical effect on antidepressant response to TMS. Conclusions: Low to moderate substance use does not have a clinically significant effect on antidepressant response to TMS. Low-level substance use should not exclude individuals with depression from receiving TMS.

Accelerated 5x5 repetitive Transcranial Magnetic Stimulation (rTMS; five stimulation sessions per day for five days) is an effective treatment for Major Depressive Disorder (MDD), and has efficacy comparable to conventional once-daily rTMS. Considering the heterogeneity of symptoms in patients with MDD, it is critical to determine how accelerated 5x5 and conventional rTMS affect depression symptom domains. We compared symptom change over time in patients treated with either accelerated 5x5 rTMS (25 total sessions, n = 40) or conventional once-daily rTMS administered over six weeks (30 total sessions, n = 135). Accelerated 5x5 patients received either prolonged intermittent theta burst stimulation (piTBS) or personalized "resonant frequency" (RF) stimulation. Mixed-effects linear models were built to compare the two protocols, with the primary outcome variables being the Inventory of Depression Symptomology Self-Report (IDS), the Ruminative Response Scale (RRS), and the Profile of Mood States - Brief (POMS), yielding measures of 14 unique depression symptom domains. Both protocols led to similar improvements in all 14 depression symptom domains (all interaction term p-values > .05). Subsequent exploratory analyses demonstrated that accelerated 5x5 and conventional rTMS may differ in the time courses of their effects on anxiety, rumination, mood, depression, and vigor (p-values < .05, uncorrected). These results suggested that accelerated 5x5 rTMS has a similar efficacy in alleviating 14 depression symptom domains compared to conventional once-daily rTMS, and that either protocol may be appropriate for MDD patients with a variety of symptom profiles.

ABSTRACT Background: Low intensity focused ultrasound (FUS) offers a noninvasive method for directly modulating deep brain structures with millimeter-scale precision, potentially addressing a major limitation of existing noninvasive neuromodulation approaches. The amygdala is a key node in affective neurocircuitry and a compelling target for psychiatric intervention. We conducted a first in human active controlled trial (NCT05147142) of amygdala-targeted FUS in patients with major depressive disorder, examining safety and target engagement. Methods: Ten participants with major depressive disorder completed a single-blind randomized crossover trial with blinded symptom ratings, comparing imaging guided FUS targeting the right amygdala versus left primary somatosensory cortex as an active control. FUS comprised two 10 minute applications within diagnostic ultrasound safety limits. Primary outcomes were safety and target engagement assessed with BOLD fMRI during sonication, post-sonication arterial spin labeling (ASL) and resting state functional connectivity. Secondary and exploratory outcomes included symptom change and imaging x symptom relationships. Results: Nine participants completed both sessions. No serious adverse events occurred; neurological, neuropsychological, and MRI safety assessments were unremarkable. Adverse events were more frequent after amygdala than control sonication (p=0.028); one participant experienced clinical worsening following amygdala sonication and required monitoring. Amygdala sonication produced greater perfusion change in the targeted amygdala compared to the control region (p<0.001), and ipsilateral hippocampus (p<0.001). BOLD fMRI during sonication demonstrated engagement of ventromedial prefrontal and rostral anterior cingulate regions, while post sonication resting state connectivity decreased between basolateral amygdala and sensorimotor regions (corrected ps<0.05). Symptom improvement did not differ between conditions, but exploratory imaging x symptom relationships were significant. Spontaneous reports of calm, clarity, or lightness occurred after amygdala but not control sonication (p<0.001). Conclusions: Amygdala targeted FUS produced anatomically specific, multimodal evidence of neuromodulation relative to active control, with a manageable safety profile. Convergent target and circuit level signals support further development of FUS as a precision approach for modulating deep brain targets in psychiatric disorders. Key words: low-intensity focused ultrasound, amygdala, neuroimaging, depression, anxiety

Background: Individuals receiving buprenorphine treatment for opioid use disorder (OUD) remain at high risk for treatment discontinuation and return to opioid use. Transcranial magnetic stimulation (TMS) has shown efficacy in reducing craving and substance use in other substance use disorders, but its application in OUD remains limited and the neural mechanism underlying its therapeutic effects is poorly understood. Determining the feasibility and generalizability of TMS in patients receiving buprenorphine - the most commonly prescribed medication for OUD - is therefore critical. This protocol aims to address these issues in a clinical trial of weekly TMS sessions for OUD. Methods: We will enroll up to 120 individuals with OUD taking buprenorphine in a randomized, single-blind, sham-controlled trial of left dorsolateral prefrontal cortex (DLPFC)-targeted intermittent theta burst stimulation (iTBS). Participants will receive active or sham iTBS weekly (2 sessions of 1800 pulses each applied once per week x 8 weeks, 16 sessions total) with pre- and post-iTBS assessments (10, 12, 20 weeks) of craving, opioid use, and treatment retention. A subset of individuals will undergo optional pre- and post-iTBS neuroimaging. The study will be conducted at an academic medical center and a private outpatient TMS clinic. Aims: Our primary aim is to determine whether 16 sessions of active iTBS applied to the left DLPFC results in reduced craving and opioid use, and higher treatment retention, relative to sham. In a secondary aim, we will also examine whether iTBS-related changes in craving are associated with changes in functional connectivity between the left DLPFC and both the dorsal striatum and anterior cingulate cortex. Discussion: By evaluating the feasibility and efficacy of a weekly TMS protocol that aligns with routine care and focuses on patients maintained on buprenorphine, this study addresses key limitations of prior TMS research in OUD. Furthermore, the inclusion of neuroimaging will help characterize the neural mechanisms underlying TMS-related changes in craving. Trial registration: This clinical trial is registered at ClinicalTrials.Gov; ID NCT07457489; date of registration: 03/02/2026.

Major depressive disorder (MDD) is strongly associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, systemic inflammation, and gut microbiota dysbiosis. Although selective serotonin reuptake inhibitors such as escitalopram are standard treatments, their efficacy is often constrained by partial response and gastrointestinal adverse effects. In this 12-week, randomized, double-blind, placebo-controlled trial, we evaluated the clinical efficacy and microecological mechanisms of adjunctive Lactiplantibacillus plantarum PS128 (PS128; 6*1010CFU/day) in MDD patients on stable escitalopram therapy. Adjunctive PS128 significantly enhanced clinical response compared to placebo, yielding substantial reductions in HAMD-17 and MADRS, alongside a higher remission rate. 16S rRNA sequencing and PICRUSt2 profiling revealed that PS128 enriched key short-chain fatty acid producers (Faecalibacterium, Coprococcus), counteracting the Klebsiella expansion seen in placebo. Functionally, PS128 up-regulated neuroprotective cofactor, B vitamins, biosynthesis and down-regulated the neurotoxic kynurenine pathway. Network analysis demonstrated that PS128 maintained a resilient, integrated microbial co-occurrence topology, whereas the placebo network showed structural segregation. This stabilized ecosystem attenuated peripheral inflammatory signaling and normalized salivary cortisol levels. Overall, adjunctive PS128 augments escitalopram efficacy by enhancing gut network stability, supporting cellular energetics, and modulating neuroendocrine activity, offering a promising multimodal strategy for MDD.

Suicidal behavior results from complex behavioral and biological changes. Previous cross-sectional studies indicate that proinflammatory immunobiological factors are often increased in close temporal proximity to a suicide attempt. Suicidal individuals may also exhibit a biological trait vulnerability to stress and inflammation, due to persistent epigenetic modifications. We enrolled 130 individuals with major depressive disorder (MDD), 83 with suicidal behavior at intake, and followed them for 12 months with up to eight clinical assessments. Quantification of plasma inflammatory markers and metabolites was performed by high-sensitivity electrochemiluminescence and Ultra High-Performance-Liquid-Mass Spectrometry (UPLC-MS), respectively. Epigenetic changes were identified using Illumina EPIC arrays. We identified 15 genes with altered DNA-methylation associated with suicidal behavior and attempts at baseline. Childhood trauma predicted lifetime suicide attempts and was associated with altered methylation of seven genes. Increased neutrophils and lower plasma serotonin at baseline predicted future suicide attempts over the following year (neutrophil estimate = 0.42, P = 0.016; serotonin OR = 0.58, 95% CI: 0.39-1.13). Utilizing biomarkers from baseline and epigenetic data from the genes with highest predictive values (STBD1 ,PRDM8, and TRIM15), we achieved an area under the curve (AUC) of 0.84 for suicide attempts over the year. Suicidal behavior in MDD was associated with specific epigenetic signatures. Several of the identified genes, such as MAD1L1, have been implicated in psychiatric disease, suicidal behavior and the immune response. These findings support the usefulness of epigenetic and immunometabolic blood markers for identifying suicidal individuals in clinical settings, potentially enhancing preventative efforts.