OPEN Foundation

Menu
Search
Close this search box.

Psychology

Ayahuasca: pharmacology, neuroscience and therapeutic potential

March 11, 2016 / Anxiety Disorders / PTSD, Ayahuasca, Depressive Disorders, Neuroscience, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Ayahuasca is the Quechua name for a tea obtained from the vine Banisteriopsis caapi, and used for ritual purposes by the indigenous populations of the Amazon. The use of a variation of the tea that combines B. caapi with the leaves of the shrub Psychotria viridis has experienced unprecedented expansion worldwide for its psychotropic properties. This preparation contains the psychedelic 5-HT2A receptor agonist N,N-dimethyltryptamine (DMT) from P. viridis, plus β-carboline alkaloids with monoamine-oxidase-inhibiting properties from B. caapi. Acute administration induces a transient modified state of consciousness characterized by introspection, visions, enhanced emotions and recollection of personal memories. A growing body of evidence suggests that ayahuasca may be useful to treat substance use disorders, anxiety and depression. Here we review the pharmacology and neuroscience of ayahuasca, and the potential psychological mechanisms underlying its therapeutic potential. We discuss recent findings indicating that ayahuasca intake increases certain mindfulness facets related to acceptance and to the ability to take a detached view of one’s own thoughts and emotions. Based on the available evidence, we conclude that ayahuasca shows promise as a therapeutic tool by enhancing self-acceptance and allowing safe exposure to emotional events. We postulate that ayahuasca could be of use in the treatment of impulse-related, personality and substance use disorders and also in the handling of trauma. More research is needed to assess the full potential of ayahuasca in the treatment of these disorders.

Domínguez-Clavé, E., Soler, J., Elices, M., Pascual, J. C., Álvarez, E., de la Fuente Revenga, M., … & Riba, J. (2016). Ayahuasca: pharmacology, neuroscience and therapeutic potential. Brain Research Bulletin. http://dx.doi.org/10.1016/j.brainresbull.2016.03.002
Link to full text

Verbal Memory Impairment in Polydrug Ecstasy Users: A Clinical Perspective

February 23, 2016 / MDMA, Papers, Psychology, Publications / By / , , , , , ,

Abstract

BACKGROUND:

Ecstasy use has been associated with short-term and long-term memory deficits on a standard Word Learning Task (WLT). The clinical relevance of this has been debated and is currently unknown. The present study aimed at evaluating the clinical relevance of verbal memory impairment in Ecstasy users. To that end, clinical memory impairment was defined as decrement in memory performance that exceeded the cut-off value of 1.5 times the standard deviation of the average score in the healthy control sample. The primary question was whether being an Ecstasy user (E-user) was predictive of having clinically deficient memory performance compared to a healthy control group.

METHODS:

WLT data were pooled from four experimental MDMA studies that compared memory performance during placebo and MDMA intoxication. Control data were taken from healthy volunteers with no drug use history who completed the WLT as part of a placebo-controlled clinical trial. This resulted in a sample size of 65 E-users and 65 age- and gender-matched healthy drug-naïve controls. All participants were recruited by similar means and were tested at the same testing facilities using identical standard operating procedures. Data were analyzed using linear mixed-effects models, Bayes factor, and logistic regressions.

RESULTS:

Findings were that verbal memory performance of placebo-treated E-users did not differ from that of controls, and there was substantial evidence in favor of the null hypothesis. History of use was not predictive of memory impairment. During MDMA intoxication of E-users, verbal memory was impaired.

CONCLUSION:

The combination of the acute and long-term findings demonstrates that, while clinically relevant memory impairment is present during intoxication, it is absent during abstinence. This suggests that use of Ecstasy/MDMA does not lead to clinically deficient memory performance in the long term. Additionally, it has to be investigated whether the current findings apply to more complex cognitive measures in diverse ‘user categories’ using a combination of genetics, imaging techniques and neuropsychological assessments.

Kuypers, K. P., Theunissen, E. L., van Wel, J. H., Perna, E. B. D. S. F., Linssen, A., Sambeth, A., … & Ramaekers, J. G. (2016). Verbal Memory Impairment in Polydrug Ecstasy Users: A Clinical Perspective. PloS one, 11(2), e0149438. http://dx.doi.org/10.1371/journal.pone.0149438

Link to full text

Effects of 3,4-methylenedioxymethamphetamine on socioemotional feelings, authenticity, and autobiographical disclosure in healthy volunteers in a controlled setting

February 15, 2016 / MDMA, Papers, Psychology, Publications / By / , , , , ,

Abstract

The drug 3,4-methylenedioxymethamphetamine (MDMA, “ecstasy”, “molly”) is a widely used illicit drug and experimental adjunct to psychotherapy. MDMA has unusual, poorly understood socioemotional effects, including feelings of interpersonal closeness and sociability. To better understand these effects, we conducted a small (n=12) within-subjects double-blind placebo controlled study of the effects of 1.5 mg/kg oral MDMA on social emotions and autobiographical disclosure in a controlled setting. MDMA displayed both sedative- and stimulant-like effects, including increased self-report anxiety. At the same time, MDMA positively altered evaluation of the self (i.e. increasing feelings of authenticity) while decreasing concerns about negative evaluation by others (i.e. decreasing social anxiety). Consistent with these feelings, MDMA increased how comfortable participants felt describing emotional memories. Overall, MDMA produced a prosocial syndrome that seemed to facilitate emotional disclosure and that appears consistent with the suggestion that it represents a novel pharmacological class.

Baggott, M. J., Coyle, J. R., Siegrist, J. D., Garrison, K. J., Galloway, G. P., & Mendelson, J. E. (2016). Effects of 3, 4-methylenedioxymethamphetamine on socioemotional feelings, authenticity, and autobiographical disclosure in healthy volunteers in a controlled setting. Journal of psychopharmacology (Oxford, England). dx.doi.org/10.1177/0269881115626348

Link to full text

Time course of pharmacokinetic and hormonal effects of inhaled high-dose salvinorin A in humans.

February 15, 2016 / Neuroscience, Papers, Psychology, Publications, Salvia / Salvinorin A / By / , , , ,

Abstract

Salvinorin A is a kappa opioid agonist and the principal psychoactive constituent of the Salvia divinorum plant, which has been used for hallucinogenic effects. Previous research on salvinorin A pharmacokinetics likely underestimated plasma levels typically resulting from the doses administered due to inefficient vaporization and not collecting samples during peak drug effects. Six healthy adults inhaled a single high dose of vaporized salvinorin A (n = 4, 21 mcg/kg; n = 2, 18 mcg/kg). Participant- and monitor-rated effects were assessed every 2 min for 60 min post-inhalation. Blood samples were collected at 13 time points up to 90 min post-inhalation. Drug levels peaked at 2 min and then rapidly decreased. Drug levels were significantly, positively correlated with participant and monitor drug effect ratings. Significant elevations in prolactin were observed beginning 5 min post-inhalation and peaking at 15 min post-inhalation. Cortisol showed inconsistent increases across participants. Hormonal responses were not well correlated with drug levels. This is the first study to demonstrate a direct relationship between changes in plasma levels of salvinorin A and drug effects in humans. The results confirm the efficacy of an inhalation technique for salvinorin A.

Johnson, M. W., MacLean, K. A., Caspers, M. J., Prisinzano, T. E., & Griffiths, R. R. (2016). Time course of pharmacokinetic and hormonal effects of inhaled high-dose salvinorin A in humans. Journal of psychopharmacology (Oxford, England). http://dx.doi.org/10.1177/0269881116629125

Link to full text

From mice to men: can ketamine enhance resilience to stress?

February 15, 2016 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By /

Abstract

The rapid antidepressant properties of intravenous ketamine have ignited high hopes from researchers, clinicians, and patients alike. While bottom-up patient demand has led some clinicians to offer repeated ketamine infusions directly to patients, academic commentators have warned against premature clinical adoption (1), at times likening the field’s enthusiasm to the misguided use of stimulants or opiates to induce short-term depression relief. The rapidity of ketamine’s antidepressant onset (2-hours post-infusion) is impressive, but effects dissipate almost as rapidly (3-7 days).

Price, R. B. (2016). From mice to men: can ketamine enhance resilience to stress?. Biological Psychiatry. http://dx.doi.org/10.1016/j.biopsych.2016.02.011
Link to full text

The therapeutic potentials of ayahuasca: possible effects against various diseases of civilization

February 8, 2016 / Ayahuasca, Papers, Psychology, Publications, Substance Use Disorder / By / , ,

Abstract

Ayahuasca is an Amazonian psychoactive brew of two main components. Its active agents are β-carboline and tryptamine derivatives. As a sacrament, ayahuasca is still a central element of many healing ceremonies in the Amazon Basin and its ritual consumption has become common among the mestizo populations of South America. Ayahuasca use amongst the indigenous people of the Amazon is a form of traditional medicine and cultural psychiatry. During the last two decades, the substance has become increasingly known among both scientists and laymen, and currently its use is spreading all over in the Western world. In the present paper we describe the chief characteristics of ayahuasca, discuss important questions raised about its use, and provide an overview of the scientific research supporting its potential therapeutic benefits. A growing number of studies indicate that the psychotherapeutic potential of ayahuasca is based mostly on the strong serotonergic effects, whereas the sigma-1 receptor agonist effect of its active ingredient dimethyltryptamine raises the possibility that the ethnomedical observations on the diversity of treated conditions can be scientifically verified. Moreover, in the right therapeutic or ritual setting with proper preparation and mindset of the user, followed by subsequent integration of the experience, ayahuasca has proven effective in the treatment of substance dependence. This article has two important take-home messages: 1) the therapeutic effects of ayahuasca are best understood from a bio-psycho-socio-spiritual model, and 2) on the biological level ayahuasca may act against chronic low grade inflammation and oxidative stress via the sigma-1 receptor which can explain its widespread therapeutic indications.

Frecska, E., Bokor, P., & Winkelman, M. (2016). The therapeutic potentials of ayahuasca: possible effects against various diseases of civilization. Frontiers in Pharmacology, 7, 35. http://dx.doi.org/10.3389/fphar.2016.00035
Link to full text

Should ketamine be used for the clinical treatment of depression?

February 5, 2016 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , ,

Abstract

OBJECTIVE: There has been widespread interest from the public and media in the potential of ketamine as a novel treatment for depression. This paper reviews whether current evidence supports the use of ketamine for the clinical treatment of depression.

CONCLUSIONS: Clinical trials have investigated the use of intravenous ketamine for the treatment of depressive symptoms over the past 15 years. However, there remain many unanswered questions regarding its effectiveness, safety, and the route, dose and regimen for repeated administration. Experts have also raised concerns regarding ketamine’s adverse effects, abuse potential and the risk of addiction. At this stage, the use of ketamine in the treatment of depression remains in the realm of research settings.

Arunogiri, S., Keks, N. A., & Hope, J. (2016). Should ketamine be used for the clinical treatment of depression?. Australasian Psychiatry, http://dx.doi.org/10.1177/1039856216629839.

Link to full text

The paradoxical psychological effects of lysergic acid diethylamide (LSD).

February 5, 2016 / LSD, Papers, Psychology, Publications / By / , , , , ,

Abstract

BACKGROUND: Lysergic acid diethylamide (LSD) is a potent serotonergic hallucinogen or psychedelic that modulates consciousness in a marked and novel way. This study sought to examine the acute and mid-term psychological effects of LSD in a controlled study.

METHOD: A total of 20 healthy volunteers participated in this within-subjects study. Participants received LSD (75 µg, intravenously) on one occasion and placebo (saline, intravenously) on another, in a balanced order, with at least 2 weeks separating sessions. Acute subjective effects were measured using the Altered States of Consciousness questionnaire and the Psychotomimetic States Inventory (PSI). A measure of optimism (the Revised Life Orientation Test), the Revised NEO Personality Inventory, and the Peter’s Delusions Inventory were issued at baseline and 2 weeks after each session.

RESULTS: LSD produced robust psychological effects; including heightened mood but also high scores on the PSI, an index of psychosis-like symptoms. Increased optimism and trait openness were observed 2 weeks after LSD (and not placebo) and there were no changes in delusional thinking.

CONCLUSIONS: The present findings reinforce the view that psychedelics elicit psychosis-like symptoms acutely yet improve psychological wellbeing in the mid to long term. It is proposed that acute alterations in mood are secondary to a more fundamental modulation in the quality of cognition, and that increased cognitive flexibility subsequent to serotonin 2A receptor (5-HT2AR) stimulation promotes emotional lability during intoxication and leaves a residue of ‘loosened cognition’ in the mid to long term that is conducive to improved psychological wellbeing.

Carhart-Harris, R. L., Kaelen, M., Bolstridge, M., Williams, T. M., Williams, L. T., Underwood, R., … & Nutt, D. J. (2016). The paradoxical psychological effects of lysergic acid diethylamide (LSD). Psychological medicine, 1-12. http://dx.doi.org/10.1017/S0033291715002901

Link to full text

Psychedelics

February 3, 2016 / Depressive Disorders, LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By /

Abstract

Psychedelics (serotonergic hallucinogens) are powerful psychoactive substances that alter perception and mood and affect numerous cognitive processes. They are generally considered physiologically safe and do not lead to dependence or addiction. Their origin predates written history, and they were employed by early cultures in many sociocultural and ritual contexts. After the virtually contemporaneous discovery of (5R,8R)-(+)-lysergic acid-N,N-diethylamide (LSD)-25 and the identification of serotonin in the brain, early research focused intensively on the possibility that LSD and other psychedelics had a serotonergic basis for their action. Today there is a consensus that psychedelics are agonists or partial agonists at brain serotonin 5-hydroxytryptamine 2A receptors, with particular importance on those expressed on apical dendrites of neocortical pyramidal cells in layer V. Several useful rodent models have been developed over the years to help unravel the neurochemical correlates of serotonin 5-hydroxytryptamine 2A receptor activation in the brain, and a variety of imaging techniques have been employed to identify key brain areas that are directly affected by psychedelics. Recent and exciting developments in the field have occurred in clinical research, where several double-blind placebo-controlled phase 2 studies of psilocybin-assisted psychotherapy in patients with cancer-related psychosocial distress have demonstrated unprecedented positive relief of anxiety and depression. Two small pilot studies of psilocybin-assisted psychotherapy also have shown positive benefit in treating both alcohol and nicotine addiction. Recently, blood oxygen level-dependent functional magnetic resonance imaging and magnetoencephalography have been employed for in vivo brain imaging in humans after administration of a psychedelic, and results indicate that intravenously administered psilocybin and LSD produce decreases in oscillatory power in areas of the brain’s default mode network.

Nichols, D. E. (2016). Psychedelics. Pharmacological reviews, 68(2), 264-355. http://dx.doi.org/10.1124/pr.115.011478

Link to full text

Effects of MDMA Injections on the Behavior of Socially-Housed Long-Tailed Macaques (Macaca fascicularis)

February 3, 2016 / MDMA, Papers, Psychology, Publications / By / , , ,

Abstract

3,4-methylenedioxy-N-methyl amphetamine (MDMA) is one of the few known molecules to increase human and rodent prosocial behaviors. However, this effect has never been assessed on the social behavior of non-human primates. In our study, we subcutaneously injected three different doses of MDMA (1.0, 1.5 or 2.0mg/kg) to a group of three, socially housed, young male long-tailed macaques. More than 200 hours of behavioral data were recorded, during 68 behavioral sessions, by an automatic color-based video device that tracked the 3D positions of each animal and of a toy. This data was then categorized into 5 exclusive behaviors (resting, locomotion, foraging, social contact and object play). In addition, received and given social grooming was manually scored. Results show several significant dose-dependent behavioral effects. At 1.5mg/kg only, MDMA induces a significant increase in social grooming behavior, thus confirming the prosocial effect of MDMA in macaques. Additionally, at 1.5 and 2.0 mg/kg MDMA injection substantially decreases foraging behavior, which is consistent with the known anorexigenic effect of this compound. Furthermore, at 2.0 mg/kg MDMA injection induces an increase in locomotor behavior, which is also in accordance with its known stimulant property. Interestingly, MDMA injected at 1.0mg/kg increases the rate of object play, which might be interpreted as a decrease of the inhibition to manipulate a unique object in presence of others, or, as an increase of the intrinsic motivation to manipulate this object. Together, our results support the effectiveness of MDMA to study the complex neurobiology of primates’ social behaviors.

Ballesta, S., Reymond, G., Pozzobon, M., & Duhamel, J. R. (2016). Effects of MDMA Injections on the Behavior of Socially-Housed Long-Tailed Macaques (Macaca fascicularis). PloS one, 11(2), e0147136. http://dx.doi.org/10.1371/journal.pone.0147136
Link to full text

interested in becoming a trained psychedelic-assisted therapist?

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

REGISTER NOW