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Boris D. Heifets

37 papers in the library · 1,656 citations · publishing 2016-2026

Papers

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Serotonergic psychedelics induce distinct patterns of metabolic activity and covariance within biologically informed rat brain networks

Nature Communications August 3, 2026 Frederik Gudmundsen, Julia Czurylo, Daniel Ryskamp Rijsketic et al.

Serotonergic psychedelics show therapeutic potential across neuropsychiatric disorders despite transient acute effects. These compounds share serotonin 2 A receptor agonism but differ in broader pharmacology, motivating a systematic comparison of their neurobiological effects. Here, we use [18 F]FDG-PET in rats to assess acute and one-week effects of psilocybin, LSD, and 2C-B on brain metabolic...

Dreaming during anaesthesia: a scoping review.

British Journal of Anaesthesia August 1, 2026 Pilleriin Sikka, Sherry Hu, Boris D. Heifets

Dreaming during anaesthesia has been documented for over a century, yet it remains poorly understood. This scoping review synthesises evidence on the frequency, phenomenology, predictors, outcomes, and neural correlates of anaesthesia dreaming. We systematically searched multiple databases for studies examining anaesthesia dreaming, including clinical trials, observational studies, and...

Low-Dose Buprenorphine Following Ketamine Treatment for Suicidal Ideation in Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial.

The American journal of psychiatry June 1, 2026 Jason M Tucciarone, Igor D. Bandeira, Christine Blasey et al. 5 citations

Ketamine rapidly reduces suicidal ideation in major depressive disorder (MDD), but its effects are transient. Preclinical and clinical studies suggest that ketamine's antidepressant and antisuicidal effects may be partly mediated by mu-opioid receptor (MOR) modulation. The authors investigated the efficacy and safety of low-dose sublingual buprenorphine, a partial MOR agonist, as a follow-on...

General Anesthesia and Discrete Components of Ketamine Neurophysiology.

JAMA Psychiatry June 1, 2026 Ben Deverett, Duan Li, Theresa R. Lii et al. 1 citation

Ketamine has well-known dissociative, analgesic, and antidepressant properties, but it is unknown whether the neurophysiologic effects that are associated with these properties can be modulated separately from one another. Considering that specific cortical oscillations have been associated with specific therapeutic effects, modulating selective aspects of ketamine neurophysiology could inform...

R-MDDMA is a Safer Analogue of MDMA with Therapeutic Potential.

ACS Chemical Neuroscience May 6, 2026 Maxemiliano V. Vargas, Cassandra J. Hatzipantelis, Lee E. Dunlap et al.

Recent clinical evidence suggests that racemic 3,4-methylenedioxymethamphetamine (MDMA) might be useful for treating a range of neuropsychiatric diseases including post-traumatic stress disorder (PTSD) and depression. However, concerns about its abuse potential stemming from its monoamine releasing properties have hampered its clinical development. Thus, safer analogues of racemic MDMA with...

Feasibility of a Multicomponent Protocol to Promote Dreaming during Surgical Anesthesia

Anesthesiology February 3, 2026 Pilleriin Sikka, May Ching Ngo, Sherry Hu et al. 1 citation

BACKGROUND: Dreaming during anesthesia is common and may have mental health benefits. However, systematic research on its incidence and outcomes in clinical settings remains limited. This study implemented a standardized propofol-based, electroencephalography (EEG)-guided emergence bundle to facilitate a preemergence state conducive to dreaming, integrating it into routine care to assess...

No evidence of immediate or persistent analgesic effect from a single dose of psilocybin in three mouse models of pain

Nature Communications January 22, 2026 Nicholas Gregory, Tyler E. Girard, Akila Ram et al. 5 citations

The psychedelic psilocybin may have lasting therapeutic effects for patients with chronic pain syndromes. Some preclinical data suggest these putative benefits derive from direct analgesic effects; however, this possibility has not been comprehensively tested in preclinical models. Here, we evaluated the analgesic properties of a single exposure to psilocybin at acute and chronic time points in...

CNSC-36. PSILOCYBIN INDUCES SUSTAINED GLIOMA GROWTH THROUGH SEROTONERGIC AND TRKB PATHWAYS

Neuro-Oncology November 1, 2025 Richard Drexler, Belgin Yalçın, Rebecca Mancusi et al.

Abstract High-grade gliomas are the most aggressive form of brain tumors, and neuronal activity has emerged as a driver of glioma pathophysiology. Activity-dependent glioma growth results from paracrine factor signaling and bona fide neuron-to-glioma synapses that integrate glioma cells into brain-wide neuronal circuits. Here, we report how glioma cells integrate into serotonergic (5-HT)...

History, pharmacology and therapeutic mechanisms of 3,4‐methylenedioxymethamphetamine (MDMA)

British Journal of Pharmacology October 21, 2025 Austen B Casey, Boris D. Heifets 3 citations

The illicit drug 3,4-methylenedioxymethamphetamine (MDMA) has recently shown promising efficacy as an adjunct to psychotherapy for posttraumatic stress disorder (PTSD), although the underlying mechanisms are poorly defined. In this review, we contextualize the emergence of MDMA-assisted psychotherapy (MDMA-AT) within 20th century psychiatry and trace its journey from assisting with military...

Methodological considerations for interpreting ketamine-naltrexone trials in depression

The International Journal of Neuropsychopharmacology October 1, 2025 Igor D. Bandeira, Luke A. Jelen, Jason M Tucciarone et al. 4 citations

Igor D Bandeira, MD, PhD, Luke A Jelen, MD, PhD, Jason M Tucciarone, MD, PhD, Boris D Heifets, MD, PhD, Carolyn I Rodriguez, MD, PhD, Alan F Schatzberg, MD

The psychoplastogen tabernanthalog induces neuroplasticity without proximate immediate early gene activation.

Nature Neuroscience September 1, 2025 Isak K Aarrestad, Lindsay P. Cameron, Ethan M Fenton et al.

Nonhallucinogenic psychoplastogens, such as tabernanthalog (TBG), are being developed as potentially safer, more scalable alternatives to psychedelics for promoting neuronal growth and treating various brain conditions. Currently, it is unclear whether 5-hydroxytryptamine 2A (5-HT2A) receptors and immediate early gene (IEG) activation have a role in the neuroplasticity-promoting effects of...

General anesthesia dissociates discrete components of ketamine neurophysiology

medRxiv August 7, 2025 Ben Deverett, Duan Li, Theresa R. Lii et al. preprint

Structured Abstract Importance Ketamine has well known dissociative, analgesic, and antidepressant properties, but it is unknown whether the neurophysiologic effects that are associated with these properties can be modulated separately from one another. Given prior studies that link specific cortical oscillations with specific therapeutic effects, it is likely that modulating selective aspects...

Opioids diminish the placebo antidepressant response: Observational post hoc findings from a randomized controlled ketamine trial.

Journal of Affective Disorders July 15, 2025 Theresa R. Lii, Josephine R. Flohr, Robin L. Okada et al. 1 citation

The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo...

Psilocybin has no immediate or persistent analgesic effect in acute and chronic mouse pain models

bioRxiv (Cold Spring Harbor Laboratory) July 7, 2025 Akila Ram, Austen B Casey, Robert C. Malenka et al. 2 citations preprint

Abstract The psychedelic psilocybin may have lasting therapeutic effects for patients with chronic pain syndromes. Some clinical and preclinical data suggest these putative benefits derive from direct analgesic effects. However, this possibility has not been comprehensively tested in preclinical models. Here, we show that psilocybin is not analgesic over a range of doses across multiple pain...

Ketamine evokes acute behavioral effects via μ-opioid receptor expressing neurons of the central amygdala.

Biological Psychiatry May 5, 2025 Matthew B Pomrenze, Sam Vaillancourt, Pierre Llorach et al. 11 citations

Ketamine has anesthetic, analgesic, and antidepressant properties which may involve multiple neuromodulatory systems. In humans, the opioid receptor (OR) antagonist naltrexone blocks the antidepressant effect of ketamine. This mechanism may differentiate ketamine from other NMDA receptor antagonists. Animal models that reflect OR-dependent behavioral effects of ketamine may shed light on the...

A multi-institutional investigation of psilocybin’s effects on mouse behavior

bioRxiv (Cold Spring Harbor Laboratory) April 9, 2025 Odilia D Lu, Katrina White, Kendall Raymond et al. 18 citations preprint

ABSTRACT Studies reporting novel therapeutic effects of psychedelic drugs are rapidly emerging. However, the reproducibility and reliability of these findings could remain uncertain for years. Here, we implemented a multi-institutional collaborative approach to define the robust and replicable effects of the psychedelic drug psilocybin on mouse behavior. Five laboratories performed the same...

Negative Affect Circuit Subtypes and Neural, Behavioral, and Affective Responses to MDMA: A Randomized Clinical Trial.

JAMA Network Open April 1, 2025 Xue Zhang, Laura M Hack, Claire Bertrand et al. 10 citations

Rapidly acting therapeutics like 3,4-methylenedioxymethamphetamine (MDMA) are promising treatments for disorders such as posttraumatic stress disorder (PTSD). However, understanding who benefits most and the underlying neural mechanisms remains a critical gap. Stratifying individuals by neural circuit profiles could help differentiate neural, behavioral, and affective responses to MDMA,...

Maintenance Intramuscular Ketamine-Assisted Psychotherapy, a Retrospective Chart Review of Efficacy, Adverse Events, and Dropouts from a Community Practice.

Journal of Psychoactive Drugs November 22, 2024 Wesley C Ryan, Boris D. Heifets 2 citations

The use of ketamine and ketamine-assisted psychotherapy (KAP) for treatment of depression has grown dramatically, though much of these data are short term. The clinical profile of maintenance treatment remains poorly characterized. We assessed maintenance KAP for efficacy, tolerability, and reasons for dropout. This observational study retrospectively analyzed electronic health records from an...

Opioids Diminish the Placebo Antidepressant Response: A Post Hoc Analysis of a Randomized Controlled Ketamine Trial.

medRxiv : the preprint server for health sciences November 2, 2024 Theresa R. Lii, Josephine R. Flohr, Robin L. Okada et al. preprint

The endogenous opioid system is thought to play a role in the placebo antidepressant response. A recent trial comparing the rapid antidepressant effects of ketamine versus placebo in surgical patients, some of whom were on chronic opioid therapy, revealed a substantial placebo effect. This finding provided an opportunity to test the hypothesis that opioid agonist exposure interacts with placebo...

5-HT2C receptors in the nucleus accumbens constrain the rewarding effects of MDMA.

bioRxiv : the preprint server for biology October 22, 2024 Matthew B Pomrenze, Sam Vaillancourt, Juliana S Salgado et al. 1 citation preprint

MDMA is a promising adjunct to psychotherapy and has well-known abuse liability, although less than other amphetamine analogs. While the reinforcing dopamine (DA)-releasing properties of MDMA are on par with methamphetamine (METH), MDMA is a far more potent serotonin (5-HT) releaser, via the 5-HT transporter (SERT). MDMA-mediated 5-HT release in a major reward center, the nucleus accumbens...

Expectancy Effects in Psychedelic Trials.

Biological psychiatry. Cognitive neuroscience and neuroimaging May 1, 2024 Balázs Szigeti, Boris D. Heifets 62 citations

Clinical trials of psychedelic compounds like psilocybin, lysergic acid diethylamide (LSD), and N,N-dimethyltrptamine (DMT) have forced a reconsideration of how nondrug factors, such as participant expectations, are measured and controlled in mental health research. As doses of these profoundly psychoactive substances increase, so does the difficulty in concealing the treatment condition in the...

MDMA enhances empathy-like behaviors in mice via 5-HT release in the nucleus accumbens.

Science Advances April 26, 2024 Ben Rein, Kendall Raymond, Cali Boustani et al. 37 citations

MDMA (3,4-methylenedioxymethamphetamine) is a psychoactive drug with powerful prosocial effects. While MDMA is sometimes termed an "empathogen," empirical studies have struggled to clearly demonstrate these effects or pinpoint underlying mechanisms. Here, we paired the social transfer of pain and analgesia-behavioral tests modeling empathy in mice-with region-specific neuropharmacology,...

Opioid receptor expressing neurons of the central amygdala gate behavioral effects of ketamine in mice.

bioRxiv : the preprint server for biology March 6, 2024 Matthew B Pomrenze, Sam Vaillancourt, Pierre Llorach et al. 1 citation preprint

Ketamine has anesthetic, analgesic, and antidepressant properties which may involve multiple neuromodulatory systems. In humans, the opioid receptor (OR) antagonist naltrexone blocks the antidepressant effect of ketamine. It is unclear whether naltrexone blocks a direct effect of ketamine at ORs, or whether normal functioning of the OR system is required to realize the full antidepressant...

UNRAVELing the synergistic effects of psilocybin and environment on brain-wide immediate early gene expression in mice.

Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology November 1, 2023 Daniel Ryskamp Rijsketic, Austen B Casey, Daniel A. N. Barbosa et al. 49 citations

The effects of context on the subjective experience of serotonergic psychedelics have not been fully examined in human neuroimaging studies, partly due to limitations of the imaging environment. Here, we administered saline or psilocybin to mice in their home cage or an enriched environment, immunofluorescently-labeled brain-wide c-Fos, and imaged iDISCO+ cleared tissue with light sheet...

Randomized trial of ketamine masked by surgical anesthesia in patients with depression

Nature Mental Health October 19, 2023 Theresa R. Lii, Ashleigh E. Smith, Josephine R. Flohr et al. 94 citations

Ketamine may have antidepressant properties, but its acute psychoactive effects complicate successful masking in placebo-controlled trials. Here we present a single-center, parallel-arm, triple-masked, randomized, placebo-controlled trial assessing the antidepressant efficacy of intravenous ketamine masked by surgical anesthesia (ClinicalTrials.gov, NCT03861988). Adult patients (N = 40) with...