OPEN Foundation

Mushrooms / Psilocybin

New study may explain magic mushrooms' effects

New research by a group of mainly Britisch scientists, based on fMRI brain scans, has shown that the use of psilocybin (the active constituent of magic mushrooms) decreases the activity of certain parts of the brain in test subjects. Brain activity decreased especially in those parts that are involved in the managing and filtering of information.

This may explain why users often report that under the influence of magic mushrooms they experience impressions and feelings that were previously unnoticed. Logically, when the brain’s ability to filter and handle information is decreased, more information may reach our consciousness. This may also explain why users often report new insights after the use of magic mushrooms, sometimes having therapeutic effects.

Another indication for the therapeutic effects of magic mushrooms is that brain activity also decreased in the medial prefrontal cortex, a brain part that is often hyperactive in patients suffering from depression.

Remarkably, these new results confirm the ideas of Aldous Huxley (1894-1963). Huxley saw the brain as a ‘reducing valve’, filtering and making information more manageable for our consciousness. He posed that psychedelic drugs might decrease these reducing properties of the brain.

Click here for the abstract and a link to the full article.

Hallucinogen use predicts reduced recidivism among substance-involved offenders under community corrections supervision

Abstract

Hallucinogen-based interventions may benefit substance use populations, but contemporary data informing the impact of hallucinogens on addictive behavior are scarce. Given that many individuals in the criminal justice system engage in problematic patterns of substance use, hallucinogen treatments also may benefit criminal justice populations. However, the relationship between hallucinogen use and criminal recidivism is unknown. In this longitudinal study, we examined the relationship between naturalistic hallucinogen use and recidivism among individuals under community corrections supervision with a history of substance involvement (n=25,622). We found that hallucinogen use predicted a reduced likelihood of supervision failure (e.g. noncompliance with legal requirements including alcohol and other drug use) while controlling for an array of potential confounding factors (odds ratio (OR)=0.60 (0.46, 0.79)). Our results suggest that hallucinogens may promote alcohol and other drug abstinence and prosocial behavior in a population with high rates of recidivism.

Hendricks, P. S., Clark, C. B., Johnson, M. W., Fontaine, K. R. & Cropsey, K. L. (2014). Hallucinogen use predicts reduced recidivism among substance-involved offenders under community corrections supervision. Journal of Psychopharmacology, 28(1), 62-66. http://dx.doi.org/10.1177/0269881113513851
Link to full text

Psilocybin – Summary of knowledge and new perspectives

Abstract

Psilocybin, a psychoactive alkaloid contained in hallucinogenic mushrooms, is nowadays given a lot of attention in the scientific community as a research tool for modeling psychosis as well as due to its potential therapeutic effects. However, it is also a very popular and frequently abused natural hallucinogen. This review summarizes all the past and recent knowledge on psilocybin. It briefly deals with its history, discusses the pharmacokinetics and pharmacodynamics, and compares its action in humans and animals. It attempts to describe the mechanism of psychedelic effects and objectify its action using modern imaging and psychometric methods. Finally, it describes its therapeutic and abuse potential.

Tylš, F., Páleníček, T., & Horáček, J. (2014). Psilocybin – Summary of knowledge and new perspectives. European Neuropsychopharmacology, 24, 342-365. http://dx.doi.org/10.1016/j.euroneuro.2013.12.006

Link to full text

Serotonergic hyperactivity as a potential factor in developmental, acquired and drug-induced synesthesia

Abstract

Though synesthesia research has seen a huge growth in recent decades, and tremendous progress has been made in terms of understanding the mechanism and cause of synesthesia, we are still left mostly in the dark when it comes to the mechanistic commonalities (if any) among developmental, acquired and drug-induced synesthesia. We know that many forms of synesthesia involve aberrant structural or functional brain connectivity. Proposed mechanisms include direct projection and disinhibited feedback mechanisms, in which information from two otherwise structurally or functionally separate brain regions mix. We also know that synesthesia sometimes runs in families. However, it is unclear what causes its onset. Studies of psychedelic drugs, such as psilocybin, LSD and mescaline, reveal that exposure to these drugs can induce synesthesia. One neurotransmitter suspected to be central to the perceptual changes is serotonin. Excessive serotonin in the brain may cause many of the characteristics of psychedelic intoxication. Excessive serotonin levels may also play a role in synesthesia acquired after brain injury. In brain injury sudden cell death floods local brain regions with serotonin and glutamate. This neurotransmitter flooding could perhaps result in unusual feature binding. Finally, developmental synesthesia that occurs in individuals with autism may be a result of alterations in the serotonergic system, leading to a blockage of regular gating mechanisms. I conclude on these grounds that one commonality among at least some cases of acquired, developmental and drug-induced synesthesia may be the presence of excessive levels of serotonin, which increases the excitability and connectedness of sensory brain regions.

Brogaard, B. (2013). Serotonergic hyperactivity as a potential factor in developmental, acquired and drug-induced synesthesia. Frontiers in Human Neuroscience, 7, 1-13. http://dx.doi.org/10.3389/fnhum.2013.00657
Link to full text

The induction of synaesthesia with chemical agents: a systematic review

Abstract

Despite the general consensus that synaesthesia emerges at an early developmental stage and is only rarely acquired during adulthood, the transient induction of synaesthesia with chemical agents has been frequently reported in research on different psychoactive substances. Nevertheless, these effects remain poorly understood and have not been systematically incorporated. Here we review the known published studies in which chemical agents were observed to elicit synaesthesia. Across studies there is consistent evidence that serotonin agonists elicit transient experiences of synaesthesia. Despite convergent results across studies, studies investigating the induction of synaesthesia with chemical agents have numerous methodological limitations and little experimental research has been conducted. Cumulatively, these studies implicate the serotonergic system in synaesthesia and have implications for the neurochemical mechanisms underlying this phenomenon but methodological limitations in this research area preclude making firm conclusions regarding whether chemical agents can induce genuine synaesthesia.

Luke, D. P., & Terhune, D. B. (2013). The induction of synaesthesia with chemical agents: a systematic review. Frontiers in Psychology, 4, 1-11. http://dx.doi.org/10.3389/fpsyg.2013.00753
Link to full text

Broadband cortical desynchronization underlies the human psychedelic state

Abstract

Psychedelic drugs produce profound changes in consciousness, but the underlying neurobiological mechanisms for this remain unclear. Spontaneous and induced oscillatory activity was recorded in healthy human participants with magnetoencephalography after intravenous infusion of psilocybin—prodrug of the nonselective serotonin 2A receptor agonist and classic psychedelic psilocin. Psilocybin reduced spontaneous cortical oscillatory power from 1 to 50 Hz in posterior association cortices, and from 8 to 100 Hz in frontal association cortices. Large decreases in oscillatory power were seen in areas of the default-mode network. Independent component analysis was used to identify a number of resting-state networks, and activity in these was similarly decreased after psilocybin. Psilocybin had no effect on low-level visually induced and motor-induced gamma-band oscillations, suggesting that some basic elements of oscillatory brain activity are relatively preserved during the psychedelic experience. Dynamic causal modeling revealed that posterior cingulate cortex desynchronization can be explained by increased excitability of deep-layer pyramidal neurons, which are known to be rich in 5-HT2A receptors. These findings suggest that the subjective effects of psychedelics result from a desynchronization of ongoing oscillatory rhythms in the cortex, likely triggered by 5-HT2A receptor-mediated excitation of deep pyramidal cells.

Muthukumaraswamy, S. D., Carhart-Harris, R. L., Moran, R. J., Brookes, M. J., Williams, T. M., Errtizoe, D., … & Feilding, A. (2013). Broadband cortical desynchronization underlies the human psychedelic state. The Journal of Neuroscience, 33(38), 15171-15183. 10.1523/JNEUROSCI.2063-13.2013
Link to full text

A proposal to evaluate mechanistic efficacy of hallucinogens in addiction treatment

Abstract

Current treatments for addiction are frequently ineffective. Hallucinogenic therapy has been indicated as helpful for a range of substance use disorders, yet this approach remains understudied and publicly unavailable. It is nonetheless a promising treatment, which has significant, long-term beneficial effects with single doses and a profile characterized by general safety, low toxicity, and non-addictiveness. However, pharmacological interventions, such as hallucinogens, should not be offered if the same effects (e.g. psychological insights/mystical experiences) and outcomes (e.g. decreased drug use) could be achieved absent pharmacological intervention. To date, there have been no clinical comparisons of drug-induced altered states with non-drug-induced states for addiction treatment. We propose and then outline a clinical trial to address this gap in knowledge. The proposed design would evaluate abstinence outcomes in a population of prescription opioid abusers after exposure to one of three conditions: a drug-induced altered state using psilocybin, a non-drug-induced altered state via hyperventilation (Holotropic Breathwork), and an active placebo with niacin. The outcomes of such a study would reveal important differences in therapeutic potential by discriminating hallucinogen-dependent effects from those psychological effects resulting from altered states.

Burdick, B. V., & Adinoff, B. (2013). A proposal to evaluate mechanistic efficacy of hallucinogens in addiction treatment. The American Journal of Drug and Alcohol Abuse, 39(5), 291-297. http://dx.doi.org/10.3109/00952990.2013.811513
Link to full text

Psychedelics and Mental Health: A Population Study

Abstract

Background
The classical serotonergic psychedelics LSD, psilocybin, mescaline are not known to cause brain damage and are regarded as non-addictive. Clinical studies do not suggest that psychedelics cause long-term mental health problems. Psychedelics have been used in the Americas for thousands of years. Over 30 million people currently living in the US have used LSD, psilocybin, or mescaline.

Objective
To evaluate the association between the lifetime use of psychedelics and current mental health in the adult population.

Method
Data drawn from years 2001 to 2004 of the National Survey on Drug Use and Health consisted of 130,152 respondents, randomly selected to be representative of the adult population in the United States. Standardized screening measures for past year mental health included serious psychological distress (K6 scale), mental health treatment (inpatient, outpatient, medication, needed but did not receive), symptoms of eight psychiatric disorders (panic disorder, major depressive episode, mania, social phobia, general anxiety disorder, agoraphobia, posttraumatic stress disorder, and non-affective psychosis), and seven specific symptoms of non-affective psychosis. We calculated weighted odds ratios by multivariate logistic regression controlling for a range of sociodemographic variables, use of illicit drugs, risk taking behavior, and exposure to traumatic events.

Results
21,967 respondents (13.4% weighted) reported lifetime psychedelic use. There were no significant associations between lifetime use of any psychedelics, lifetime use of specific psychedelics (LSD, psilocybin, mescaline, peyote), or past year use of LSD and increased rate of any of the mental health outcomes. Rather, in several cases psychedelic use was associated with lower rate of mental health problems.

Conclusion
We did not find use of psychedelics to be an independent risk factor for mental health problems.

Krebs, T. S., & Johansen, P. Ø. (2013) Psychedelics and Mental Health: A Population Study. PLoS ONE, 8(8), 1-9. http://dx.doi.org/10.1371/journal.pone.0063972
Link to full text

Phylogenetic inference and trait evolution of the psychedelic mushroom genus Psilocybe sensu lato (Agaricales)

Abstract

The genus Psilocybe contains iconic species of fungi renowned for their hallucinogenic properties. Recently, Psilocybe also included non-hallucinogenic species that have since been shifted to the genus Deconica. Here, we reconstruct a multigene phylogeny for Psilocybe, Deconica, and other exemplars of the families Hymenogastraceae and Strophariaceae sensu stricto (s. str.), using three nuclear markers (nLSU-rRNA, 5.8S rRNA, and rpb1). Our results confirm the monophyly of Deconica within Strophariaceae s. str., as well as numerous robust infrageneric relationships. Psilocybe is also recovered as a monophyletic group in the Hymenogastraceae, in which two principal lineages are recognized, including several nested subgroups. Most sections of Psilocybe following classifications based on morphological features are not supported in these analyses. Ancestral character state reconstruction analyses suggest that basidiospore shape in frontal view and spore wall thickness, commonly used to characterize sections in Deconica and Psilocybe, are homoplastic. Chrysocystidia, sterile cells located in the hymenium, evolved on at least two occasions in the Strophariaceae s. str., including in a novel lineage of Deconica.

Ramírez-Cruz, V. Guzmán, G., Villalobos-Arámbula, A. R., Rodríguez, A.,  Matheny, P. B., Sánchez-García, M., & Guzmán-Dávalos, L. (2013). Phylogenetic inference and trait evolution of the psychedelic mushroom genusPsilocybesensu lato (Agaricales). Botany, 91, 573-591. http://dx.doi.org/10.1139/cjb-2013-0070
Link to full text

Spatiotemporal Brain Dynamics of Emotional Face Processing Modulations Induced by the Serotonin 1A/2A Receptor Agonist Psilocybin

Abstract

Emotional face processing is critically modulated by the serotonergic system. For instance, emotional face processing is impaired by acute psilocybin administration, a serotonin (5-HT) 1A and 2A receptor agonist. However, the spatiotemporal brain mechanisms underlying these modulations are poorly understood. Here, we investigated the spatiotemporal brain dynamics underlying psilocybin-induced modulations during emotional face processing. Electrical neuroimaging analyses were applied to visual evoked potentials in response to emotional faces, following psilocybin and placebo administration. Our results indicate a first time period of strength (i.e., Global Field Power) modulation over the 168–189 ms poststimulus interval, induced by psilocybin. A second time period of strength modulation was identified over the 211–242 ms poststimulus interval. Source estimations over these 2 time periods further revealed decreased activity in response to both neutral and fearful faces within limbic areas, including amygdala and parahippocampal gyrus, and the right temporal cortex over the 168–189 ms interval, and reduced activity in response to happy faces within limbic and right temporo-occipital brain areas over the 211–242 ms interval. Our results indicate a selective and temporally dissociable effect of psilocybin on the neuronal correlates of emotional face processing, consistent with a modulation of the top-down control.

Bernasconi, F., Schmidt, A., Pokorny, T., Kometer, M., Seifritz, E., & Vollenweider, F. X. (2013). Spatiotemporal brain dynamics of emotional face processing modulations induced by the serotonin 1A/2A receptor agonist psilocybin. Cerebral Cortex, bht178. 10.1093/cercor/bht178
Link to full text

interested in becoming a trained psychedelic-assisted therapist?

Management of Psychedelic-Related Complications - Online Event - Nov 20th