Nitrous Oxide for the Treatment of Major Depressive Disorder
DepressionMajor Depressive DisorderThe investigators are conducting a randomized controlled trial to evaluate the antidepressant effects of nitrous oxide in people with Major Depressive Disorder (MDD). MDD is a global medical condition that causes significant health and economic burden. Recent studies have shown that a single dose of ketamine, an NMDA-antagonist, has fast and long lasting anti-depressant effect. Nitrous oxide, another NMDA-antagonist, is widely used for anesthesia and analgesia, safer to administer and has fewer side effects than ketamine. A randomized controlled crossover feasibility study showed significant reduction in depressive symptoms at 2 and 24 hours after a single 1-hour treatment session of inhaled nitrous oxide compared with placebo. Nitrous oxide is inexpensive and can be safely administered by any trained clinician. If found to be efficacious, it could be used to provide rapid anti-depressant effect whilst the benefit of traditional anti-depressants has its delayed effect. Another potential application could be in acutely suicidal patients. This investigated-initiated phase 2b trial will enable confirmation and extension of the findings from the feasibility study, and identify the optimal dose and regimen in a broader population of those with MDD. Participants will be randomized to receive a weekly 1-hour inhalational sessions of either nitrous oxide or placebo (oxygen-air mixture) for 4 weeks, and the nitrous group will be further randomly assigned to a dose of 50% nitrous oxide or 25% nitrous oxide. Depression severity will be assessed by a blinded observer pre-treatment and at weekly intervals during and for 4 weeks after treatment using the Hamilton Depression Rating Scale.
Maintenance of Response After rTMS for Depression Using tDCS
Major Depressive DisorderThis is a double-blind, multi-site, randomized controlled trial (RCT) that will recruit 200 participants.The purpose of the RCT will be to evaluate the efficacy of transcranial direct current stimulation (tDCS) in combination with mindfulness meditation compared to sham tDCS to maintain wellness following an acute course of repetitive transcranial magnetic stimulation (rTMS) for up to 6 months.
Group Metacognitive Therapy vs Clinical Management for Depression
Major Depressive DisorderThe main aims of the study are to (1) compare the effectiveness of Group metacognitive therapy (GMCT) treatment to that of clinical management and (2) explore patterns of change and investigate factors associated with treatment outcome
Personalized High-Definition Transcranial Direct Current Stimulation (HD-tDCS) Treatment for Major...
Major Depressive EpisodeAdolescents with mood disorders experiencing major depressive episode have poor efficacy of medication treatment. High-Definition Transcranial Direct Current Stimulation (HD-tDCS) has been proven adjuvant efficacy in patients with major depressive episode. However, the optimal evidence-based stimulation parameters have not been clearly defined, which greatly limits the efficacy of HD-tDCS in the treatment of major depressive episode.This trial will compare a novel form of accurate and personalized HD-tDCS treatment protocol guided by neuroimaging biomarkers to the routine stimulation(stimulation target is L-DLPFC, central electrode is anode).The personalized selection of stimulation site, central electrode polarity will be determined by neuroimaging biomarkers. The study aims to propose a novel personalized neuroimaging-guided HD-tDCS strategy, to evaluate the efficacy and safety of the treatment, further to understand the biological mechanism of the personalized HD-tDCS treatment.
Cognitive Fitness for Depression in Older Adults
Depression MildDepressive Disorder2 moreThis research is being done to determine if computerized administered cognitive fitness activities will improve thinking and depression in older depressed adults who are being treated with antidepressants. The investigators are also interested in whether participating in the treatment will result in changes to brain activity measured with magnetic resonance imaging (MRI).
rTMS for Suicidality in Opioid Use Disorder
Major Depressive DisorderOpioid-use DisorderThis trial is a randomized, double blind, controlled pilot study that will compare bilateral theta burst stimulation (TBS) and sham treatment for patients with opioid use disorder (OUD) and Major Depressive Disorder (MDD) experiencing suicidality.
Neural Mechanisms of Intermittent Theta Burst Stimulation in the Core Depression Network
Major Depressive DisorderRepetitive Transcranial magnetic stimulation (TMS) uses magnetic fields to modulate brain activity. A novel form of repetitive TMS (rTMS), intermittent theta burst stimulation (iTBS), has emerged as a promising new treatment for depression. This technique may be advantageous due to its very short duration and potentially stronger effect on brain activity in comparison with standard rTMS. However, the exact effect of iTBS on the activity of the brain in clinical populations remains poorly understood. This project aims to improve understanding of the mechanisms of action of iTBS by comparing its neuronal effect to sham treatment in 22 individuals with a diagnosis of major depressive episode, using positron emission tomography (PET) and magnetic resonance imaging (MRI) in a double-blind cross-over experiment, followed by a 6-week daily treatment course of iTBS.
Microdosing Psychedelics to Improve Mood
Major Depressive DisorderThis trial aims to examine the safety and efficacy of small (2mg) sub-hallucinogenic doses of psilocybin in people with Major Depressive Disorder.
The Effects of Videogames on Depression Symptoms and Brain Dynamics
Major Depressive DisorderThe purpose of the study is to evaluate the effects of a game-based digital-therapeutics (DTx) medical software device on the symptoms of depression in adults with confirmed major depressive disorder.
Dorsomedial Prefrontal Neuromodulation in Treatment-resistant Depression
Treatment-resistant DepressionMajor Depressive DisorderMajor depressive disorder (MDD) is a common and troublesome disorder, with high risk of physical and psychiatric comorbidity. At least one-third of patients could not achieve a response after several antidepressant trials, so-called treatment-refractory depression (TRD). The high-frequency repetitive transcranial magnetic stimulation (rTMS) or intermittent theta-burst stimulation (iTBS) at left-sided dorsolateral prefrontal cortex (DLPFC) have a response rate of 40-60%. Obviously, not all TRD patients achieve the remitted state after treatment with antidepressants or DLPFC-rTMS, which may result from the heterogeneity of MDD. More and more evidence, such as brain lesion studies, deep brain stimulation, open-labeled rTMS case series, and neuroimaging studies, suggests that dorsomedial prefrontal cortex (DMPFC) might play a more central role in the pathophysiology of major depression. The DMPFC demonstrated as a "dorsal nexus" phenomenon in depression, which means a unique brain region where cortical networks for affect regulation, default mode control and cognitive control coverage in depressed subjects but not in healthy persons. In addition, another meta-analysis of resting-state functional MRI (fMRI) demonstrated the abnormal functional connectivity from DMPFC. These abnormalities of networks were highly associated with several depressive symptoms such as anhedonia, emotional regulation, somatic markers, rumination, self-reflection, poor attention and poor decision-making. However, only a handful of studies investigated the brain stimulation targeting DMPFC and the further changes in brain functional connectivity. The clinical efficacy and the fMRI changes of prolonged intermittent theta-burst stimulation (piTBS) and 20Hz- rTMS targeting bilateral DMPFC were investigated, and the predictive value of baseline networks by fMRI for antidepressant responses was also assessed to find a reliable approach to gauge treatment response prospectively.