OPEN Foundation

Menu
Search
Close this search box.

Psychology

Entheogens, Mysticism, and Neuroscience

August 26, 2014 / Ayahuasca, LSD, Mescaline / Cacti, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By /

Abstract

Entheogens or psychedelic drugs such as lysergic acid diethylamide (LSD) and psilocybin are associated with mystical states of experience. Drug laws currently limit research, but important new work is under way at major biomedical research facilities showing that entheogens reliably occasion mystical experiences and thereby allow research into brain states during these experiences. Are drug-occasioned mystical experiences neurologically the same as more traditional mystical states? Are there phenomenological and theological differences? As this research goes forward and the public becomes more widely aware of its achievements, religious scholars and experts in science and religion will be called upon to interpret the philosophical and theological presuppositions that underpin this research and the significance of the findings that flow from it.

Cole-Turner, R. (2014). Entheogens, Mysticism, and Neuroscience. Zygon: Journal of Religion and Science, 49(3), 642-651. http://dx.doi.org/10.1111/zygo.12110
Link to full text

Ketamine administration in depressive disorders: a systematic review and meta-analysis

July 20, 2014 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , , , , , , , ,

Abstract

Introduction
Ketamine’s efficacy in depressive disorders has been established in several controlled trials. The aim of the present study was to determine whether or not ketamine administration significantly improves depressive symptomatology in depression and more specifically in major depressive disorder (MDD), bipolar depression, resistant depression (non-ECT studies), and as an anesthetic agent in electroconvulsive therapy (ECT) for resistant depression (ECT studies). Secondary outcomes were the duration of ketamine’s effect, the efficacy on suicidal ideations, the existence of a dose effect, and the safety/tolerance of the treatment.

Methods
Studies were included if they met the following criteria (without any language or date restriction): design: randomized controlled trials, intervention: ketamine administration, participants: diagnosis of depression, and evaluation of severity based on a validated scale. We calculated standardized mean differences (SMDs) with 95 % confidence intervals (CIs) for each study. We used fixed and random effects models. Heterogeneity was assessed using the I2 statistic.

Results
We included nine non-ECT studies in our quantitative analysis (192 patients with major depressive disorder and 34 patients with bipolar depression). Overall, depression scores were significantly decreased in the ketamine groups compared to those in the control groups (SMD = −0.99; 95 % CI −1.23, −0.75; p < 0.01). Ketamine’s efficacy was confirmed in MDD (resistant to previous pharmacological treatments or not) (SMD = −0.91; 95 % CI −1.19,−0.64; p < 0.01), in bipolar depression (SMD = −1.34; 95 % CI −1.94, −0.75), and in drug-free patients as well as patients under medication. Four ECT trials (118 patients) were included in our quantitative analysis. One hundred and three patients were diagnosed with major depressive disorder and 15 with bipolar depression. Overall, depression scores were significantly improved in the 58 patients receiving ketamine in ECT anesthesia induction compared to the 60 patients (SMD = −0.56; 95 % CI −1.10, −0.02; p = 0.04; I2 = 52.4 %). The duration of ketamine’s effects was assessed in only two non-ECT studies and seemed to persist for 2–3 days; this result needs to be confirmed. Three of four studies found significant decrease of suicidal thoughts and one found no difference between groups, but suicidal ideations were only studied by the suicide item of the depressive scales. It was not possible to determine a dose effect; 0.5 mg/kg was used in the majority of the studies. Some cardiovascular events were described (mostly transient blood pressure elevation that may require treatment), and ketamine’s use should remain cautious in patients with a cardiovascular history.

Conclusion
The present meta-analysis confirms ketamine’s efficacy in depressive disorders in non-ECT studies, as well as in ECT studies. The results of this first meta-analysis are encouraging, and further studies are warranted to detail efficacy in bipolar disorders and other specific depressed populations. Middle- and long-term efficacy and safety have yet to be explored. Extrapolation should be cautious: Patients included had no history of psychotic episodes and no history of alcohol or substance use disorders, which is not representative of all the depressed patients that may benefit from this therapy.

Fond, G., Loundou, A., Rabu, C., Macgregor, A., Lançon, C., Brittner, M. … Boyer, L. (2014). Ketamine administration in depressive disorders: a systematic review and meta-analysis. Psychopharmacology, 231, 3663-3676. http://dx.doi.org/10.1007/s00213-014-3664-5
Link to full text

Recent advances in the neuropsychopharmacology of serotonergic hallucinogens

July 15, 2014 / DMT, LSD, Mescaline / Cacti, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By /

Abstract

Serotonergic hallucinogens, such as (+)-lysergic acid diethylamide, psilocybin, and mescaline, are somewhat enigmatic substances. Although these drugs are derived from multiple chemical families, they all produce remarkably similar effects in animals and humans, and they show cross-tolerance. This article reviews the evidence demonstrating the serotonin 5-HT2A receptor is the primary site of hallucinogen action. The 5-HT2A receptor is responsible for mediating the effects of hallucinogens in human subjects, as well as in animal behavioral paradigms such as drug discrimination, head twitch response, prepulse inhibition of startle, exploratory behavior, and interval timing. Many recent clinical trials have yielded important new findings regarding the psychopharmacology of these substances. Furthermore, the use of modern imaging and electrophysiological techniques is beginning to help unravel how hallucinogens work in the brain. Evidence is also emerging that hallucinogens may possess therapeutic efficacy.

Halberstadt, A. L. (2014). Recent advances in the neuropsychopharmacology of serotonergic hallucinogens. Behavioural Brain Research, 277, 99-120. http://dx.doi.org/10.1016/j.bbr.2014.07.016
Link to full text

The Effects of Ayahuasca Ritual Participation on Gay and Lesbian Identity

July 14, 2014 / Ayahuasca, Papers, Psychology, Publications / By /

Abstract

The practice of drinking ayahuasca—a psychoactive brew indigenous to the Amazon—has been investigated in several studies and shown to have positive long-term effects on mental states, and a particularly strong positive effect on perceptions of identity. This article discusses if these previous findings can be found in the experience of gay people, who are often taught by their culture and religion that their lifestyles, values, and sexual orientation are unacceptable. The qualitative study examined the interview responses of 17 self-identified gay and lesbian participants who had drunk ayahuasca in a ceremonial context within the past three years, regarding their self-perceptions and integration of group beliefs. Participants drank either in shamanic or Santo Daime ceremonies or, in the case of one participant, with an Afro-Brazilian group that used ayahuasca. Participants reported affirmation of their sexual orientation, and no participants reported negative effects on perception of identity. Additional positive effects in other areas of their lives, which they attributed to ayahuasca sessions, contributed to the overall positive outcomes that were reported by this group as a result of their ritual participation.

Cavnar, C. (2014). The effects of ayahuasca ritual participation on gay and lesbian identity. Journal of psychoactive drugs, 46(3), 252-260. https://dx.doi.org/10.1080/02791072.2014.920117

Link to full text

Enhanced repertoire of brain dynamical states during the psychedelic experience

July 2, 2014 / Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By / , , , ,

Abstract

The study of rapid changes in brain dynamics and functional connectivity (FC) is of increasing interest in neuroimaging. Brain states departing from normal waking consciousness are expected to be accompanied by alterations in the aforementioned dynamics. In particular, the psychedelic experience produced by psilocybin (a substance found in `magic mushrooms`) is characterized by unconstrained cognition and profound alterations in the perception of time, space and selfhood. Considering the spontaneous and subjective manifestation of these effects, we hypothesize that neural correlates of the psychedelic experience can be found in the dynamics and variability of spontaneous brain activity fluctuations and connectivity, measurable with functional Magnetic Resonance Imaging (fMRI). Fifteen healthy subjects were scanned before, during and after intravenous infusion of psilocybin and an inert placebo. Blood-Oxygen Level Dependent (BOLD) temporal variability was assessed computing the variance and total spectral power, resulting in increased signal variability bilaterally in the hippocampi and anterior cingulate cortex. Changes in BOLD signal spectral behavior (including spectral scaling exponents) affected exclusively higher brain systems such as the default mode, executive control and dorsal attention networks. A novel framework enabled us to track different connectivity states explored by the brain during rest. This approach revealed a wider repertoire of connectivity states post-psilocybin than during control conditions. Together, the present results provide a comprehensive account of the effects of psilocybin on dynamical behaviour in the human brain at a macroscopic level and may have implications for our understanding of the unconstrained, hyper-associative quality of consciousness in the psychedelic state.

Tagliazucchi, E., Carhart-Harris, R. L., Leech, R., Nutt, D., & Chialvo, D. R. (2014). Enhanced repertoire of brain dynamical states during the psychedelic experience. Human Brain Mapping, 35(11), 5442-5456. http://dx.doi.org/10.1002/hbm.22562
Link to full text

Examining the psychological mechanisms of psilocybin-assisted smoking cessation treatment: A pilot study

July 1, 2014 / Mushrooms / Psilocybin, Papers, Psychology, Publications, Substance Use Disorder / By / , ,

Abstract

Anthropological evidence and early experimental studies suggest that structured administration of 5-HT2A agonist hallucinogens (e.g., LSD, psilocybin) may have potential in treating addictions, including alcoholism and opioid dependence. Psilocybin administration has been recently linked to persisting effects including personality change (i.e., increased NEO Openness), mood enhancement, and behavior change. The association between mood, personality, and addiction has been well documented, and suggests that psilocybin may be useful in the treatment of addiction.

Garcia-Romeu, A. P., Johnson, M. W., & Griffiths, R. R. (2014). Examining the psychological mechanisms of psilocybin-assisted smoking cessation treatment: A pilot study. Drug & Alcohol Dependence, 140, e66. http://dx.doi.org/10.1016/j.drugalcdep.2014.02.200
Link to full text

Harmine for catatonic schizophrenia. A forgotten experiment

June 30, 2014 / Depressive Disorders, Humanities & Art, Papers, Psychiatry & Medicine, Psychology, Publications / By / , ,

Abstract

The purpose of this letter is to present a lesser-known experiment suggesting a positive response of catatonic schizophrenia to Harmine, a monoamine oxidase A inhibitor(MAO-A), a study conducted by Petre Tomescu, in the late 1920’s.

 

Hostiuc, S., Buda, O., & Ion, D. A. (2014). Harmine for catatonic schizophrenia. A forgotten experiment. Schizophrenia research, 1(159), 249-250. http://dx.doi.org/10.1016/j.schres.2014.08.006

Link to full text

Efficacy of Intravenous Ketamine for Treatment of Chronic Posttraumatic Stress Disorder

June 11, 2014 / Anxiety Disorders / PTSD, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Importance  Few pharmacotherapies have demonstrated sufficient efficacy in the treatment of posttraumatic stress disorder (PTSD), a chronic and disabling condition.

Objective  To test the efficacy and safety of a single intravenous subanesthetic dose of ketamine for the treatment of PTSD and associated depressive symptoms in patients with chronic PTSD.

Design, Setting, and Participants  Proof-of-concept, randomized, double-blind, crossover trial comparing ketamine with an active placebo control, midazolam, conducted at a single site (Icahn School of Medicine at Mount Sinai, New York, New York). Forty-one patients with chronic PTSD related to a range of trauma exposures were recruited via advertisements.

Interventions  Intravenous infusion of ketamine hydrochloride (0.5 mg/kg) and midazolam (0.045 mg/kg).

Main Outcomes and Measures  The primary outcome measure was change in PTSD symptom severity, measured using the Impact of Event Scale–Revised. Secondary outcome measures included the Montgomery-Asberg Depression Rating Scale, the Clinical Global Impression–Severity and –Improvement scales, and adverse effect measures, including the Clinician-Administered Dissociative States Scale, the Brief Psychiatric Rating Scale, and the Young Mania Rating Scale.

Results  Ketamine infusion was associated with significant and rapid reduction in PTSD symptom severity, compared with midazolam, when assessed 24 hours after infusion (mean difference in Impact of Event Scale–Revised score, 12.7 [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][95% CI, 2.5-22.8]; P = .02). Greater reduction of PTSD symptoms following treatment with ketamine was evident in both crossover and first-period analyses, and remained significant after adjusting for baseline and 24-hour depressive symptom severity. Ketamine was also associated with reduction in comorbid depressive symptoms and with improvement in overall clinical presentation. Ketamine was generally well tolerated without clinically significant persistent dissociative symptoms.

Conclusions and Relevance  This study provides the first evidence for rapid reduction in symptom severity following ketamine infusion in patients with chronic PTSD. If replicated, these findings may lead to novel approaches to the pharmacologic treatment of patients with this disabling condition.

Feder, A., Parides, M. K., Murrough, J. W., Perez, A. M., Morgan, J. E., Saxena, S., … & Charney, D. S. (2014). Efficacy of intravenous ketamine for treatment of chronic posttraumatic stress disorder: a randomized clinical trial. JAMA psychiatry, 71(6), 681-688. https://dx.doi.org/10.1001/jamapsychiatry.2014.62
Link to full text[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]

Hallucinogen persisting perception disorder and the serotonergic system: A comprehensive review including new MDMA-related clinical cases

June 7, 2014 / Neuroscience, Papers, Psychology, Publications / By / , , ,

Abstract

Hallucinogen persisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered visual processing was reviewed and the majority of HPPD cases were attributed to drugs with agonistic effects on serotonergic 5-HT2A receptors. Moreover, we present 31 new HPPD cases that link HPPD to the use of ecstasy (MDMA), which is known to reverse serotonin reuptake and acts as agonist on 5-HT2A receptors. The available evidence suggests that HPPD symptoms may be a result from a misbalance of inhibitory-excitatory activity in low-level visual processing and GABA-releasing inhibitory interneurons may be involved. However, high co-morbidities with anxiety, attention problems and derealization symptoms add complexity to the etiology of HPPD. Also, other perceptual disorders that show similarity to HPPD cannot be ruled out in presentations to clinical treatment. Taken together, evidence is still sparse, though low-level visual processing may play an important role. A novel finding of this review study, evidenced by our new cases, is that ecstasy (MDMA) use may also induce symptoms of HPPD.

Litjens, R. P., Brunt, T. M., Alderliefste, G. J., & Westerink, R. H. (2014). Hallucinogen persisting perception disorder and the serotonergic system: A comprehensive review including new MDMA-related clinical cases. European Neuropsychopharmacology, 24(8), 1309-1323. https://dx.doi.org/10.1016/j.euroneuro.2014.05.008

Link to full text

Pharmacology of Hallucinations: Several Mechanisms for One Single Symptom?

June 4, 2014 / LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Psychotic Disorders, Publications / By / , , , , ,

Abstract

Hallucinations are complex misperceptions, that principally occur in schizophrenia or after intoxication induced by three main classes of drugs: psychostimulants, psychedelics, and dissociative anesthetics. There are at least three different pharmacological ways to induce hallucinations: (1) activation of dopamine D2 receptors (D2Rs) with psychostimulants, (2) activation of serotonin 5HT2A receptors (HT2ARs) with psychedelics, and (3) blockage of glutamate NMDA receptors (NMDARs) with dissociative anesthetics. In schizophrenia, the relative importance of NMDAR and D2R in the occurrence of hallucinations is still debated. Slight clinical differences are observed for each etiology. Thus, we investigated whether the concept of hallucination is homogenous, both clinically and neurobiologically. A narrative review of the literature is proposed to synthesize how the main contributors in the field have approached and tried to solve these outstanding questions. While some authors prefer one explanatory mechanism, others have proposed more integrated theories based on the different pharmacological psychosis models. In this review, such theories are discussed and faced with the clinical data. In addition, the nosological aspects of hallucinations and psychosis are addressed. We suggest that if there may be common neurobiological pathways between the different pharmacological systems that are responsible for the hallucinations, there may also be unique properties of each system, which explains the clinical differences observed.

Rolland, B., Jardri, R., Amad, A., Thomas, P., Cottencin, O., & Bordet, R. (2014). Pharmacology of Hallucinations: Several Mechanisms for One Single Symptom? Biomed Research International. http://dx.doi.org/10.1155/2014/307106
Link to full text

Online Event - Psychedelic Care in Recreational Settings - 3 October 2024

REGISTER NOW
X

interested in becoming a trained psychedelic-assisted therapist?