Background: The past few decades have seen a revived interest in psychedelic-assisted and ketamine-assisted therapy for mental health disorders, but data concerning the acute, subacute, and long-term effects of serotonergic psychedelics on cognitive functioning are scarce. This international, online study (N = 759) sought to investigate the potential acute, subacute, and long-term effects of...
Arginine vasopressin (AVP) modulates stress responsivity and social-affective behaviors, but its role in mood and trauma-related disorders remains poorly defined due to challenges in peripheral measurement. This study used copeptin, a stable, reliable, and well-validated surrogate marker of AVP secretion, to assess vasopressinergic function in a transdiagnostic sample of individuals...
NPJ Digital MedicineDecember 8, 2025Joseph Geraci, Bessi Qorri, Mike Tsay et al.
Clinical trial failures are frequently driven by patient heterogeneity and limited sample sizes that obscure treatment effects by diluting statistical power. We introduce NetraAI, a novel explainable artificial intelligence (AI) platform that integrates dynamical-systems modeling, evolutionary long-range memory feature selection, and large-language model (LLM)-generated insights, to discover...
This international online study (N=759) examined the acute, subacute, and long-term effects of psychedelic drug use on cognitive performance and mental health. Participants completed cognitive tasks assessing working memory, selective attention, and visual/spatial perception, as well as questionnaires assessing mental health outcomes and quality of life. Based on self-reported substance use,...
Subanesthetic-dose ketamine has recently been reported to improve hedonic pleasures associated with social interactions and altruism in individuals with treatment-resistant depression. However, whether ketamine-among other glutamate receptor modulators-also improves empathy and/or prosocial behavior in humans remains unknown. Under a framework grounded in neurobiology that proposes that...
This analysis sought to identify potential clinical targets for the suicide crisis. Characteristics of a useful clinical target include elevation at the time of suicide crisis and responsiveness to rapid-acting interventions. Suicidal ideation (SI), depression, and hopelessness were hypothesized to meet these criteria. Participants were 118 adults across the continuum of suicide risk, including...
Participants who received ketamine at the NIMH were among the first to receive ketamine for depression in controlled clinical trials, providing a unique opportunity to assess long-term outcomes. This analysis evaluated the relationship between participating in a ketamine clinical trial and subsequent ketamine/esketamine use after leaving the research setting. Participants seen within the NIMH...
The glutamatergic modulator ketamine is associated with changes in sleep, depression, and suicidal ideation (SI). This study sought to evaluate differences in arousal-related sleep metrics between 36 individuals with treatment-resistant major depression (TRD) and 25 healthy volunteers (HVs). It also sought to determine whether ketamine normalizes arousal in individuals with TRD and whether...
The novel mechanisms of action (MOA) derived from some recently introduced molecular targets have led to regulatory approvals for rapid acting antidepressants (RAADs) that can generate responses within hours or days, rather than weeks or months. These novel targets include the N-methyl-D-glutamate receptor antagonist ketamine, along with its enantiomers and various derivatives, and the...
Abstract Depression is disabling and highly prevalent. Intravenous (IV) ketamine displays rapid-onset antidepressant properties, but little is known regarding which patients are most likely to benefit, limiting personalized prescriptions. We identified randomized controlled trials of IV ketamine that recruited individuals with a relevant psychiatric diagnosis (e.g., unipolar or bipolar...
Suicide is a leading cause of death and morbidity worldwide, yet few interventions are available to mitigate its risk. Barriers to effective treatments involve a limited understanding of factors that predict the onset of suicidal thoughts and behaviors. In the context of suicide risk, stress is a precipitating factor that is largely overlooked in the literature. Indeed, the pathophysiology of...
Ketamine produces immediate antidepressant effects and has inspired research into next-generation treatments. Ketamine also has short term dissociative effects, in which individuals report altered consciousness and perceptions of themselves and their environment. However, whether ketamine's dissociative side effects are necessary for its antidepressant effects remains unclear. This perspective...
OBJECTIVE: Ketamine's effects on different dimensions of depressive symptomatology, including typical/melancholic and atypical depression, remain largely unknown. This study examined the effects of a single intravenous dose of ketamine on general depressive symptoms (measured using the Montgomery-Asberg Depression Rating Scale (MADRS), typical/melancholic symptoms (measured using the MADRS5),...
As a field, psychiatry is undergoing an exciting paradigm shift toward early identification and intervention that will likely minimize both the burden associated with severe mental illnesses as well as their duration. In this context, the rapid-acting antidepressant ketamine has revolutionized our understanding of antidepressant response and greatly expanded the pharmacologic armamentarium for...
No pharmacological treatments exist for active suicidal ideation (SI), but the glutamatergic modulator ketamine elicits rapid changes in SI. We developed data-driven subgroups of SI trajectories after ketamine administration, then evaluated clinical, demographic, and neurobiological factors that might predict SI response to ketamine. Data were pooled from five clinical ketamine trials....
PURPOSE: This study examined the links between 24-hour activity patterns (specifically, amplitude and timing of wrist activity) and the persisting qualities of clinical antidepressant response to the glutamatergic modulator ketamine. METHODS: Twenty-four-hour activity patterns were compared across 5 days of 24-hour activity rhythms in patients with major depressive disorder who displayed either...
Due to the heterogeneity of depressive symptoms-which can include depressed mood, anhedonia, negative cognitive biases, and altered activity levels-researchers often use a combination of depression rating scales to assess symptoms. This study sought to identify unidimensional constructs measured across rating scales for depression and to evaluate these constructs across clinical trials of a...
Ketamine’s mechanism of action was assessed using gamma power from magnetoencephalography (MEG) as a proxy measure for homeostatic balance in 35 unmedicated subjects with major depressive disorder (MDD) and 25 healthy controls enrolled in a double-blind, placebo-controlled, randomized cross-over trial of 0.5 mg/kg ketamine. MDD subjects showed significant improvements in depressive symptoms,...
Background Ketamine induces rapid and robust antidepressant effects, and many patients also describe dissociation, which is associated with antidepressant response. This follow-up study investigated whether antidepressant efficacy is uniquely related to dissociative symptom clusters. Methods Treatment-resistant patients with major depressive disorder (MDD) or bipolar disorder (BD) (n=126) drawn...
BACKGROUND: This study sought to reproduce, in a larger sample, previous findings of a correlation between smaller raw 3-Tesla (3T) hippocampal volumes and improved antidepressant efficacy of ketamine in individuals with major depressive disorder (MDD). A secondary analysis stratified subjects according to functional BDNF rs6265 (val66met) genotype. METHODS: Unmedicated subjects with...
Objective Suicide is a public health crisis with limited treatment options. We conducted a systematic review and individual participant data meta-analysis examining the effects of a single dose of ketamine on suicidal ideation. Method Individual participant data were obtained from 10 of 11 identified comparison intervention studies (using either saline or midazolam as control). The analysis...
The rapid clinical antidepressant effects of the glutamatergic modulator ketamine may be due to its ability to restore synaptic plasticity and related effects on sleep-wake and circadian systems. Preclinical studies indicate that ketamine alters expression of circadian clock-associated molecules, and clinical studies of ketamine on plasticity-related biomarkers further suggest an association...
Identifying clinical correlates associated with reduced suicidal ideation may highlight new avenues for the treatment of suicidal thoughts. Anhedonia occurs across psychiatric diagnoses and has been associated with specific neural circuits in response to rapid-acting treatments, such as ketamine. This analysis sought to evaluate whether reductions in suicidal ideation after ketamine...
OBJECTIVE: Insomnia and disrupted sleep are associated with increased risk of suicide. The N-methyl-d-aspartate antagonist ketamine has been associated with reduced suicidal thoughts, but the mechanism of action is unknown. This study sought to evaluate differences in nocturnal wakefulness in depressed individuals who did and did not have an antisuicidal response to ketamine. METHODS:...
Current pharmacotherapies for major depressive disorder (MDD) have a distinct lag of onset that can prolong distress and impairment for patients, and realworld effectiveness trials further suggest that antidepressant efficacy is limited in many patients. All currently approved antidepressant medications for MDD act primarily through monoaminergic mechanisms, e.g., receptor/reuptake agonists or...