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Psychology

Effects of Ketamine on Brain Activity During Emotional Processing: Differential Findings in Depressed Versus Healthy Control Participants.

January 25, 2019 / Depression, Ketamine, Papers, Psychiatry, Psychology, Psychopharmacology, Publications / By / , , , , ,

Abstract

BACKGROUND:
In the search for novel treatments for depression, ketamine has emerged as a unique agent with rapid antidepressant effects. Experimental tasks involving emotional processing can be used during functional magnetic resonance imaging scanning to investigate ketamine’s effects on brain function in major depressive disorder (MDD). This study examined ketamine’s effects on functional magnetic resonance imaging activity during an emotional processing task.
METHODS:
A total of 33 individuals with treatment-resistant MDD and 24 healthy control participants (HCs) took part in this double-blind, placebo-controlled crossover study. Participants received ketamine and placebo infusions 2 weeks apart, and functional magnetic resonance imaging scans were conducted at baseline and 2 days after each infusion. Blood oxygen level-dependent signal was measured during an emotional processing task, and a linear mixed-effects model was used to analyze differences in activation among group, drug, and task-specific factors.
RESULTS:
A group-by-drug interaction was observed in several brain regions, including a right frontal cluster extending into the anterior cingulate cortex and insula. Participants with MDD had greater activity than HCs after placebo infusion but showed lower activity after ketamine infusion, which was similar to the activity in HCs after placebo. A group-by-drug-by-task condition interaction was also found, which showed further differences that varied between implicit and explicit emotional conditions.
CONCLUSIONS:
The main results indicate that ketamine had differential effects on brain activity in participants with MDD versus HCs. The pattern of activation in participants with MDD after ketamine infusion resembled the activation in HCs after placebo infusion, suggesting a normalization of function during emotional processing. The findings contribute to a better understanding of ketamine’s actions in the brain.
Reed, J. L., Nugent, A. C., Furey, M. L., Szczepanik, J. E., Evans, J. W., & Zarate Jr, C. A. (2019). Effects of ketamine on brain activity during emotional processing: differential findings in depressed versus healthy control participants. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging., 10.1016/j.bpsc.2019.01.005
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Neurochemical models of near-death experiences: A large-scalestudy based on the semantic similarity of written reports

January 20, 2019 / DMT, Ketamine, Mystical experiences, Other substances, Papers, Phenomenology, Psychiatry, Psychology, Psychopharmacology, Psychotherapy, Publications, Religious studies, Spirituality / By / , , , , , ,

Abstract

The real or perceived proximity to death often results in a non-ordinary state of consciousness characterized by phenomenological features such as the perception of leaving the body boundaries, feelings of peace, bliss and timelessness, life review, the sensation of traveling through a tunnel and an irreversible threshold. Near-death experiences (NDEs) are comparable among individuals of different cultures, suggesting an underlying neurobiological mechanism. Anecdotal accounts of the similarity between NDEs and certain drug-induced altered states of consciousness prompted us to perform a large-scale comparative analysis of these experiences. After assessing the semantic similarity between ≈15,000 reports linked to the use of 165 psychoactive substances and 625 NDE narratives, we determined that the N-methyl-D-aspartate (NMDA) receptor antagonist ketamine consistently resulted in reports most similar to those associated with NDEs. Ketamine was followed by Salvia divinorum (a plant containing a potent and selective κ receptor agonist) and a series of serotonergic psychedelics, including the endogenous serotonin 2A receptor agonist N,N-Dimethyltryptamine (DMT). This similarity was driven by semantic concepts related to consciousness of the self and the environment, but also by those associated with the therapeutic, ceremonial and religious aspects of drug use. Our analysis sheds light on the long-standing link between certain drugs and the experience of “dying“, suggests that ketamine could be used as a safe and reversible experimental model for NDE phenomenology, and supports the speculation that endogenous NMDA antagonists with neuroprotective properties may be released in the proximity of death.

Martial, C., Cassol, H., Charland-Verville, V., Pallavicini, C., Sanz, C., Zamberlan, F., … & Tagliazucchi, E. (2019). Neurochemical models of near-death experiences: A large-scale study based on the semantic similarity of written reports. Consciousness and cognition, 69, 52-69., https://doi.org/10.1016/j.concog.2019.01.011
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Trait Openness and serotonin 2A receptors in healthy volunteers: A positron emission tomography study.

January 11, 2019 / Mushrooms / Psilocybin, Papers, Personality, Psychology, Psychopharmacology, Publications / By / , , , , , ,

Abstract

Recent research found lasting increases in personality trait Openness in healthy individuals and patients after administration of the serotonin 2A receptor (5-HT2A R) agonist psilocybin. However, no studies have investigated whether 5-HT2A R availability as imaged using positron emission tomography (PET) is associated with this trait. In 159 healthy individuals (53 females), the association between 5-HT2A R binding in neocortex imaged with [18 F]altanserin or [11 C]Cimbi-36 PET and personality trait Openness was investigated using linear regression models. In these models the influence of sex on the association was also investigated. Trait Openness was assessed with the NEO Personality Inventory-Revised. No significant associations between neocortical 5-HT2A R binding and trait Openness were found for [18F]altanserin (p = 0.5) or [11 C]Cimbi-36 (p = 0.8). Pooling the data in a combined model did not substantially change our results (p = 0.4). No significant interactions with sex were found (p > 0.35). Our results indicate that differences in 5-HT2A R availability are not related to variations in trait Openness in healthy individuals. Although stimulation of the 5-HT2A R with compounds such as psilocybin may contribute to long-term changes in trait Openness, there is no evidence in favor of an association between 5-HT2A R and trait Openness.
Stenbæk, D. S., Kristiansen, S., Burmester, D., Madsen, M. K., Frokjaer, V. G., Knudsen, G. M., & Fisher, P. M. (2019). Trait Openness and serotonin 2A receptors in healthy volunteers: A positron emission tomography study. Human brain mapping., 10.1002/hbm.24511
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Effects of acute and repeated treatment with serotonin 5-HT2A receptor agonist hallucinogens on intracranial self-stimulation in rats

January 10, 2019 / Cacti / Mescaline, Depression, LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Psychopharmacology, Psychotherapy, Publications, Substance Use Disorder / By / , , , , ,

Abstract

The prototype 5-HT2A receptor agonist hallucinogens LSD, mescaline, and psilocybin are classified as Schedule 1 drugs of abuse by the U.S. Drug Enforcement Administration. Accumulating clinical evidence has also suggested that acute or repeated “microdosing” with these drugs may have utility for treatment of some mental health disorders, including drug abuse and depression. The goal of the present study was to evaluate LSD, mescaline, and psilocybin effects on intracranial self-stimulation (ICSS), a procedure that has been used to evaluate abuse-related effects of other classes of abused drugs. Effects of repeated LSD were also examined to evaluate potential changes in its own effects on ICSS or changes in effects produced by the abused psychostimulant methamphetamine or the prodepressant kappa opioid receptor (KOR) agonist U69,593. Male Sprague-Dawley rats were implanted with microelectrodes targeting the medial forebrain bundle and trained to respond under a “frequency-rate” ICSS procedure, in which many drugs of abuse increase (or “facilitate”) ICSS. In acute dose-effect and time-course studies, evidence for abuse-related ICSS facilitation was weak and inconsistent; the predominant effect of all 3 drugs was dose- and time-dependent ICSS depression. Repeated LSD treatment failed to alter either its own ICSS depressant effects or the abuse-related effects of methamphetamine; however, repeated LSD did attenuate ICSS depression by U69,593. These results extend those of previous preclinical studies to suggest weak expression of abuse-related effects by 5-HT2A agonist hallucinogens and provide supportive evidence for therapeutic effects of repeated LSD dosing to attenuate KOR-mediated depressant effects but not abuse potential of psychostimulants.

Sakloth, F., Leggett, E., Moerke, M. J., Townsend, E. A., Banks, M. L., & Negus, S. S. (2019). Effects of acute and repeated treatment with serotonin 5-HT2A receptor agonist hallucinogens on intracranial self-stimulation in rats. Experimental and clinical psychopharmacology., 10.1037/pha0000253.
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Perceived Benefits of MDMA-Assisted Psychotherapy beyond Symptom Reduction: Qualitative Follow-Up Study of a Clinical Trial for Individuals with Treatment-Resistant PTSD.

January 7, 2019 / Anxiety disorders / PTSD, MDMA, Papers, Psychiatry, Psychology, Psychopharmacology, Psychotherapy, Publications / By / , , ,

Abstract

We present select findings from a long-term follow-up qualitative study of MDMA-assisted psychotherapy for veterans, firefighters, and police officers suffering from chronic, treatment-resistant PTSD. Semi-structured qualitative interviews were conducted at participants’ one-year follow-up after a recently completed phase 2 clinical trial. Available interviews from 19 of 24 participants were analyzed. This qualitative analysis sought to complement, clarify, and expand upon the quantitative findings obtained from the Clinician Administered PTSD Scale (CAPS-IV) and supported by the Long-Term Follow-Up (LTFU) Questionnaire. Pertinent data from interview transcripts were coded and analyzed using an interpretative phenomenological analysis (IPA) methodological framework. We explore prominent thematic elements from participant accounts to better understand the outcomes experienced in this trial. All participants reported experiencing lasting personal benefits and enhanced quality of life that extend beyond quantifiable symptom reduction. We explore a range of treatment benefits beyond symptom reduction to highlight the utility of qualitative investigations of the process and effects of MDMA-assisted psychotherapy. Limitations and challenges encountered in conducting this study are discussed along with recommendations for improved qualitative research protocols in future clinical trials.
Barone, W., Beck, J., Mitsunaga-Whitten, M., & Perl, P. (2019). Perceived Benefits of MDMA-Assisted Psychotherapy beyond Symptom Reduction: Qualitative Follow-Up Study of a Clinical Trial for Individuals with Treatment-Resistant PTSD. Journal of psychoactive drugs, 1-10., https://doi.org/10.1080/02791072.2019.1580805
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The effects of ketamine on suicidality across various formulations and study settings

January 4, 2019 / Anxiety disorders / PTSD, Ketamine, Medicine, Neuroscience, Other subjects, Papers, Psychiatry, Psychology, Psychopharmacology, Psychotherapy, Publications / By / ,

Abstract

INTRODUCTION:

Suicidality and self-injurious behavior afflict patients with a wide variety of psychiatric illnesses. Currently, there are few pharmacologic treatments for suicidality and self-injurious behavior and none that treat these conditions emergently. Recently, ketamine has demonstrated efficacy in treating both depression and acute suicidal ideation. An increasing usage of ketamine, of a variety of formulations, has been studied for these indications. This article reviews the evidence for use of ketamine in self-injurious behavior and suicidality.

METHODS:

A review of the MEDLINE database for articles relating to ketamine, self-injurious behavior, suicidality, and self-harm was conducted. Additional articles were assessed via cross-reference.

RESULTS:

A total of 24 articles that included clinical trials, meta-analyses, case series, and case reports were analyzed. The majority of studies of ketamine for suicidal ideation include the intravenous route using a dose of 0.5 mg/kg over 40 minutes. These studies suggest that intravenous ketamine may be effective at reducing suicidal ideation acutely. Data on use of ketamine in the intramuscular, intranasal, and oral forms are limited and of poorer quality. Studies on these formulations contain greater variability of positive and negative results of ketamine for reducing suicidality and self-injurious behavior. The durability of the antisuicidal effects across all formulations is limited.

DISCUSSION:

Ketamine may be an effective option for the treatment of suicidal ideation in patients across inpatient, outpatient, or emergent settings. At this time, more research is needed on the efficacy of ketamine across all formulations being used in clinical practice.

Dadiomov, D., & Lee, K. (2019). The effects of ketamine on suicidality across various formulations and study settings. Mental Health Clinician, 9(1), 48-60., 10.9740/mhc.2019.01.048
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Microdosing psychedelics: personality, mental health, and creativity differences in microdosers

January 2, 2019 / Creativity, LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Personality, Psychology, Psychotherapy, Publications / By / , , , , , ,

Abstract

RATIONALE:

Microdosing psychedelics-the regular consumption of small amounts of psychedelic substances such as LSD or psilocybin-is a growing trend in popular culture. Recent studies on full-dose psychedelic psychotherapy reveal promising benefits for mental well-being, especially for depression and end-of-life anxiety. While full-dose therapies include perception-distorting properties, microdosing mayprovide complementary clinical benefits using lower-risk, non-hallucinogenic doses.

OBJECTIVES:

This pre-registered study aimed to investigate whether microdosing psychedelics is related to differences in personality, mental health, and creativity.

METHODS:

In this observational study, respondents recruited from online forums self-reported their microdosing behaviors and completed questionnaires concerning dysfunctional attitudes, wisdom, negative emotionality, open-mindedness, and mood. Respondents also performed the Unusual Uses Task to assess their creativity.

RESULTS:

Current and former microdosers scored lower on measures of dysfunctional attitudes (p < 0.001, r = – 0.92) and negative emotionality (p = 0.009, r = – 0.85) and higher on wisdom (p < 0.001, r = 0.88), openmindedness(p = 0.027, r = 0.67), and creativity (p < 0.001, r = 0.15) when compared to non-microdosing controls.

CONCLUSIONS:

These findings provide promising initial evidence that warrants controlled experimental research to directly test safety and clinical efficacy. As microdoses are easier to administer than full-doses, this new paradigm has the exciting potential to shape future psychedelic research.

Anderson, T., Petranker, R., Rosenbaum, D., Weissman, C. R., Dinh-Williams, L. A., Hui, K., … & Farb, N. A. (2018). Microdosing Psychedelics: Personality, mental health, and creativity differences in microdosers. Psychopharmacology, 1-10., 10.1007/s00213-018-5106-2
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Microdosing psychedelics: personality, mental health, and creativity differences in microdosers.

January 2, 2019 / Creativity, LSD, Mushrooms / Psilocybin, Papers, Personal development, Personality, Psychology, Psychopharmacology, Psychotherapy, Publications, Safety / By / , , , , , ,

Abstract

RATIONALE:
Microdosing psychedelics-the regular consumption of small amounts of psychedelic substances such as LSD or psilocybin-is a growing trend in popular culture. Recent studies on full-dose psychedelic psychotherapy reveal promising benefits for mental well-being, especially for depression and end-of-life anxiety. While full-dose therapies include perception-distorting properties, microdosing mayprovide complementary clinical benefits using lower-risk, non-hallucinogenic doses.
OBJECTIVES:
This pre-registered study aimed to investigate whether microdosing psychedelics is related to differences in personality, mental health, and creativity.
METHODS:
In this observational study, respondents recruited from online forums self-reported their microdosing behaviors and completed questionnaires concerning dysfunctional attitudes, wisdom, negative emotionality, open-mindedness, and mood. Respondents also performed the Unusual Uses Task to assess their creativity.
RESULTS:
Current and former microdosers scored lower on measures of dysfunctional attitudes (p < 0.001, r = – 0.92) and negative emotionality (p = 0.009, r = – 0.85) and higher on wisdom (p < 0.001, r = 0.88), openmindedness(p = 0.027, r = 0.67), and creativity (p < 0.001, r = 0.15) when compared to non-microdosing controls.
CONCLUSIONS:
These findings provide promising initial evidence that warrants controlled experimental research to directly test safety and clinical efficacy. As microdoses are easier to administer than full-doses, this new paradigm has the exciting potential to shape future psychedelic research.

Anderson, T., Petranker, R., Rosenbaum, D., Weissman, C. R., Dinh-Williams, L. A., Hui, K., … & Farb, N. A. (2019). Microdosing Psychedelics: Personality, mental health, and creativity differences in microdosers. Psychopharmacology, 236(2), 731-740., https://doi.org/10.1007/s00213-018-5106-2
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Effect of Ritualistic Consumption of Ayahuasca on Hepatic Function in Chronic Users.

December 22, 2018 / Ayahuasca, Papers, Psychology, Psychopharmacology, Publications, Safety / By / , , , , , ,

Abstract

Ayahuasca is a beverage obtained from decoctions of the liana Banisteriopsis caapi plus the shrub Psychotria viridis. This beverage contains a combination of monoamine oxidase inhibitors (harmine, harmaline, and tetrahydroharmine) and N,N-dimethyltryptamine, the main substance responsible for its visionary effect. The ritualistic use of ayahuasca is becoming a global phenomenon. Most members of ayahuasca churches consume this beverage throughout their life, and many reports have discussed the therapeutic potential of this beverage. Ayahuasca is consumed orally, and the liver, as the major organ for the metabolism and detoxification of xenobiotics absorbed from the alimentary tract, may be susceptible to injury by compounds present in the ayahuasca decoction. In this study, we evaluated biochemical parameters related to hepatic damage in the serum of 22 volunteers who consumed ayahuasca twice a month or more for at least one year. There was no significant alteration in the following parameters: alanine aminotransferase, aspartate aminotransferase, bilirubin, creatinine, urea, lactate dehydrogenase, alkaline phosphatase, and gamma glutamyl transferase. These findings indicate that chronic ayahuasca consumption in a religious context apparently does not affect hepatic function.
Mello, S. M., Soubhia, P. C., Silveira, G., Corrêa-Neto, N. F., Lanaro, R., Costa, J. L., & Linardi, A. (2018). Effect of Ritualistic Consumption of Ayahuasca on Hepatic Function in Chronic Users. Journal of psychoactive drugs, 1-9., 10.1080/02791072.2018.1557355
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