OPEN Foundation

D. Nutt

How Depression Can Be Treated with a Psychedelic Trip

If you’re interested in psychedelics, then you might have heard of the work of Robin Carhart-Harris, who conducted much of the most relevant research in the world of psychedelics together with his team at Imperial College in London.

In this look back at ICPR 2016 we will highlight the talk he held about his team’s trials with psychedelics-assisted psychotherapy, where he also showed some beautiful visuals of his team’s brain research, which happened to become some of the most famous psychedelic brain imagery known on the internet. 

Like our upcoming ICPR 2022 near Amsterdam, the edition in 2016 strove to bring together as many relevant studies from psychedelics as possible, and Carhart-Harris’ talk was most certainly a highlight. His research has been cited often and his talk was one of the best-watched from that year’s ICPR on our Youtube channel.

In his talk, Carhart-Harris talks about the results of his research – that psychedelics can cause a rise in cognitive flexibility, neuroplasticity, creative thinking, imaginative suggestibility, emotional lability, positive moods, and optimism. 

He also touches on the idea of depressive realism, a trend he has seen in patients suffering from depression. He describes their depression as a “sort of delusion”, where his patients “don’t see the world as it really is. There is this really quite evident pessimism bias, that is normalised post-treatment with psilocybin.”

A testimony of one of the participants is featured in the talk:

26:35 — ‘Although it’s early days yet, the results are amazing. I feel more confident and calm than I have in such a long time. My outlook has changed significantly too, I’m more aware that it’s pointless to get wrapped up in endless negativity. I also feel as if I’ve seen a much clearer picture. [Now] I can enjoy things the way I used to, without the cynicism, without the oppression. At its most basic. I feel like I used to before the depression.”

Brain Scans

One way to go about investigating psychedelics is by making fMRI brain scans. These scans are made of healthy and depressed individuals before, during and after a psychedelic experience. This way, the brain can be observed for changes.

Through these scans, the team got insights into the inner workings of the brain during psychedelic trips, and how they correlate with described experiences of volunteers, like ego-death. This is a type of experience in which people who are under the influence of psychedelics describe a certain loss of self, and a deeper connection with the wider universe or nature. 

Carhart’s studies have highlighted that the Default Brain Network may be connected with our sense of self – our ego –  and that the lower activity of this network during a psychedelic session may be associated with the occurrence of ego-death.

Some of the brain scans from the research team at Imperial, from 2012.

12:40 — “We see quite reliably a relationship between the magnitude of the disintegration and the default brain network. [..] The greater the disintegration of the default mode network, the greater our volunteers’ ratings of ego-dissolution. ”

During the psychedelic experience induced with psilocybin, the parts of the brain associated with the Default Brain Network show a drastic reduction in activity, often creating the experience of ego-death. The compulsive activity of the Default Brain Network also has been associated with patients that scored higher in depression ratings.

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The Default Brain Network and the Self

Robin Carhart-Harris’s argument is that the Default Brain Network may be the source of what most adult people call the ‘ego’. This network is known as the Default Mode Network because, during our daily lives, this brain network becomes more active when we are idle

The Default Mode is actually a really important part of our mental stability. This network is responsible for keeping our routines in check, making sure that our pending matters stay afloat, and that we’re not overlooking anything.

The mental activity generated by the Default Mode Network is usually stable and consistent day after day. This daily consistency in addition to the fact the DMN is the ‘standard’ mental voice, may contribute to the illusion that the Default Mode Network is the self.

12:58 — [The Default Brain Network is]: “Arguably the best candidate we have for the neural substrates of the self, or the ego, or our identity and personality.” – Robert Carhart-Harris

By analyzing the brains of participants who consumed psilocybin, Carhart’s team noticed that there was a process of renewal happening within the structure of the brain, almost like a general mind reset. This process of rebirth has been reported many times by psychedelic subjects.

17:50 — “We can think of the mind or the brain is reset in the same way that you can think of a computer is malfunctioning and throwing up an error message and you are wondering what you can do. And then you press the reset button and it comes back working nice and smooth as it should.”

In more recent years, Carhart-Harris has worked on building a more unified model of the workings of psychedelics in the brain. He founded the Psychedelic Research Group at Imperial College in London and focuses on the action of psychedelic drugs in the brain, and their clinical utility as aides to psychotherapy, with a particular focus on depression. He still studies the brain effects of LSD, psilocybin (magic mushrooms), and MDMA. 

Robin Carhart-Harris will not be speaking at ICPR 2022, but his colleague and the new head of the Psychedelic Research Group at Imperial College will: David Nutt

Notes about the author: Alexandre Perrella is a writer for Cabbanis!

Trial of Psilocybin versus Escitalopram for Depression

Abstract

Background: Psilocybin may have antidepressant properties, but direct comparisons between psilocybin and established treatments for depression are lacking.

Methods: In a phase 2, double-blind, randomized, controlled trial involving patients with long-standing, moderate-to-severe major depressive disorder, we compared psilocybin with escitalopram, a selective serotonin-reuptake inhibitor, over a 6-week period. Patients were assigned in a 1:1 ratio to receive two separate doses of 25 mg of psilocybin 3 weeks apart plus 6 weeks of daily placebo (psilocybin group) or two separate doses of 1 mg of psilocybin 3 weeks apart plus 6 weeks of daily oral escitalopram (escitalopram group); all the patients received psychological support. The primary outcome was the change from baseline in the score on the 16-item Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR-16; scores range from 0 to 27, with higher scores indicating greater depression) at week 6. There were 16 secondary outcomes, including QIDS-SR-16 response (defined as a reduction in score of >50%) and QIDS-SR-16 remission (defined as a score of ≤5) at week 6.

Results: A total of 59 patients were enrolled; 30 were assigned to the psilocybin group and 29 to the escitalopram group. The mean scores on the QIDS-SR-16 at baseline were 14.5 in the psilocybin group and 16.4 in the escitalopram group. The mean (±SE) changes in the scores from baseline to week 6 were -8.0±1.0 points in the psilocybin group and -6.0±1.0 in the escitalopram group, for a between-group difference of 2.0 points (95% confidence interval [CI], -5.0 to 0.9) (P = 0.17). A QIDS-SR-16 response occurred in 70% of the patients in the psilocybin group and in 48% of those in the escitalopram group, for a between-group difference of 22 percentage points (95% CI, -3 to 48); QIDS-SR-16 remission occurred in 57% and 28%, respectively, for a between-group difference of 28 percentage points (95% CI, 2 to 54). Other secondary outcomes generally favored psilocybin over escitalopram, but the analyses were not corrected for multiple comparisons. The incidence of adverse events was similar in the trial groups.

Conclusions: On the basis of the change in depression scores on the QIDS-SR-16 at week 6, this trial did not show a significant difference in antidepressant effects between psilocybin and escitalopram in a selected group of patients. Secondary outcomes generally favored psilocybin over escitalopram, but the analyses of these outcomes lacked correction for multiple comparisons. Larger and longer trials are required to compare psilocybin with established antidepressants.

Carhart-Harris, R., Giribaldi, B., Watts, R., Baker-Jones, M., Murphy-Beiner, A., Murphy, R., Martell, J., Blemings, A., Erritzoe, D., & Nutt, D. J. (2021). Trial of Psilocybin versus Escitalopram for Depression. The New England journal of medicine, 384(15), 1402–1411. https://doi.org/10.1056/NEJMoa2032994

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Self-blinding citizen science to explore psychedelic microdosing

Abstract

Microdosing is the practice of regularly using low doses of psychedelic drugs. Anecdotal reports suggest that microdosing enhances well-being and cognition; however, such accounts are potentially biased by the placebo effect. This study used a ‘self-blinding’ citizen science initiative, where participants were given online instructions on how to incorporate placebo control into their microdosing routine without clinical supervision. The study was completed by 191 participants, making it the largest placebo-controlled trial on psychedelics to-date. All psychological outcomes improved significantly from baseline to after the 4 weeks long dose period for the microdose group; however, the placebo group also improved and no significant between-groups differences were observed. Acute (emotional state, drug intensity, mood, energy, and creativity) and post-acute (anxiety) scales showed small, but significant microdose vs. placebo differences; however, these results can be explained by participants breaking blind. The findings suggest that anecdotal benefits of microdosing can be explained by the placebo effect.

Szigeti, B., Kartner, L., Blemings, A., Rosas, F., Feilding, A., Nutt, D. J., Carhart-Harris, R. L., & Erritzoe, D. (2021). Self-blinding citizen science to explore psychedelic microdosing. eLife, 10, e62878. https://doi.org/10.7554/eLife.62878

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First study of safety and tolerability of 3,4-methylenedioxymethamphetamine-assisted psychotherapy in patients with alcohol use disorder

Abstract

Background: 3,4-methylenedioxymethamphetamine (MDMA) therapy has qualities that make it potentially well suited for patients with addictions, but this has never been explored in a research study. We present data from the Bristol Imperial MDMA in Alcoholism (BIMA) study. This is the first MDMA addiction study, an open-label safety and tolerability proof-of-concept study investigating the potential role for MDMA therapy in treating patients with alcohol use disorder (AUD).

Aims: This study aimed to assess if MDMA-assisted psychotherapy can be delivered safely and can be tolerated by patients with AUD post detoxification. Outcomes regarding drinking behaviour, quality of life and psychosocial functioning were evaluated.

Methods: Fourteen patients with AUD completed a community alcohol detoxification and received an eight-week course of recovery-based therapy. Participants received two sessions with MDMA (187.5 mg each session). Psychological support was provided before, during and after each session. Safety and tolerability were assessed alongside psychological and physiological outcome measures. Alcohol use behaviour, mental well-being and functioning data were collected for nine months after alcohol detoxification.

Results: MDMA treatment was well tolerated by all participants. No unexpected adverse events were observed. Psychosocial functioning improved across the cohort. Regarding alcohol use, at nine months post detox, the average units of alcohol consumption by participants was 18.7 units per week compared to 130.6 units per week before the detox. This compares favourably to a previous observational study (the ‘Outcomes’ study) by the same team with a similar population of people with AUD.

Conclusions: This study provides preliminary support for the safety and tolerability of a novel intervention for AUD post detox. Further trials to examine better the therapeutic potential of this approach are now indicated.

Sessa, B., Higbed, L., O’Brien, S., Durant, C., Sakal, C., Titheradge, D., Williams, T. M., Rose-Morris, A., Brew-Girard, E., Burrows, S., Wiseman, C., Wilson, S., Rickard, J., & Nutt, D. J. (2021). First study of safety and tolerability of 3,4-methylenedioxymethamphetamine-assisted psychotherapy in patients with alcohol use disorder. Journal of psychopharmacology (Oxford, England), 35(4), 375–383. https://doi.org/10.1177/0269881121991792

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The entropic tongue: Disorganization of natural language under LSD

Abstract

Serotonergic psychedelics have been suggested to mirror certain aspects of psychosis, and, more generally, elicit a state of consciousness underpinned by increased entropy of on-going neural activity. We investigated the hypothesis that language produced under the effects of lysergic acid diethylamide (LSD) should exhibit increased entropy and reduced semantic coherence. Computational analysis of interviews conducted at two different time points after 75 μg of intravenous LSD verified this prediction. Non-semantic analysis of speech organization revealed increased verbosity and a reduced lexicon, changes that are more similar to those observed during manic psychoses than in schizophrenia, which was confirmed by direct comparison with reference samples. Importantly, features related to language organization allowed machine learning classifiers to identify speech under LSD with accuracy comparable to that obtained by examining semantic content. These results constitute a quantitative and objective characterization of disorganized natural speech as a landmark feature of the psychedelic state.

Sanz, C., Pallavicini, C., Carrillo, F., Zamberlan, F., Sigman, M., Mota, N., Copelli, M., Ribeiro, S., Nutt, D., Carhart-Harris, R., & Tagliazucchi, E. (2021). The entropic tongue: Disorganization of natural language under LSD. Consciousness and cognition, 87, 103070. https://doi.org/10.1016/j.concog.2020.103070

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Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies

Abstract

Objective: To conduct a systematic review of modern-era (post-millennium) clinical studies assessing the therapeutic effects of serotonergic psychedelics drugs for mental health conditions. Although the main focus was on efficacy and safety, study characteristics, duration of antidepressants effects across studies, and the role of the subjective drug experiences were also reviewed and presented.

Method: A systematic literature search (1 Jan 2000 to 1 May 2020) was conducted in PubMed and PsychINFO for studies of patients undergoing treatment with a serotonergic psychedelic.

Results: Data from 16 papers, representing 10 independent psychedelic-assisted therapy trials (psilocybin = 7, ayahuasca = 2, LSD = 1), were extracted, presented in figures and tables, and narratively synthesized and discussed. Across these studies, a total of 188 patients suffering either cancer- or illness-related anxiety and depression disorders (C/I-RADD), major depressive disorder (MDD), obsessive-compulsive disorder (OCD) or substance use disorder (SUD) were included. The reviewed studies established feasibility and evidence of safety, alongside promising early data of efficacy in the treatment of depression, anxiety, OCD, and tobacco and alcohol use disorders. For a majority of patients, the therapeutic effects appeared to be long-lasting (weeks-months) after only 1 to 3 treatment session(s). All studies were conducted in line with guidelines for the safe conduct of psychedelic therapy, and no severe adverse events were reported.

Conclusion: The resurrection of clinical psychedelic research provides early evidence for treatment efficacy and safety for a range of psychiatric conditions, and constitutes an exciting new treatment avenue in a health area with major unmet needs.

Andersen, K., Carhart-Harris, R., Nutt, D. J., & Erritzoe, D. (2021). Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies. Acta psychiatrica Scandinavica, 143(2), 101–118. https://doi.org/10.1111/acps.13249

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DMT alters cortical travelling waves

Abstract

Psychedelic drugs are potent modulators of conscious states and therefore powerful tools for investigating their neurobiology. N,N, Dimethyltryptamine (DMT) can rapidly induce an extremely immersive state of consciousness characterized by vivid and elaborate visual imagery. Here, we investigated the electrophysiological correlates of the DMT-induced altered state from a pool of participants receiving DMT and (separately) placebo (saline) while instructed to keep their eyes closed. Consistent with our hypotheses, results revealed a spatio-temporal pattern of cortical activation (i.e. travelling waves) similar to that elicited by visual stimulation. Moreover, the typical top-down alpha-band rhythms of closed-eyes rest were significantly decreased, while the bottom-up forward wave was significantly increased. These results support a recent model proposing that psychedelics reduce the ‘precision-weighting of priors’, thus altering the balance of top-down versus bottom-up information passing. The robust hypothesis-confirming nature of these findings imply the discovery of an important mechanistic principle underpinning psychedelic-induced altered states.

Alamia, A., Timmermann, C., Nutt, D. J., VanRullen, R., & Carhart-Harris, R. L. (2020). DMT alters cortical travelling waves. eLife, 9, e59784. https://doi.org/10.7554/eLife.59784

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The Current Status of Psychedelics in Psychiatry

Abstract

In the 1950s, the Swiss pharmaceutical company Sandoz, which employed the chemist Albert Hofmann, who discovered lysergic acid diethylamide (LSD) and the similar serotonergic psychedelic psilocybin, made these drugs available to the psychiatric research community as the products Delysid and Indocybin, respectively. By the 1960s, these drugs had caused a revolution in brain science and psychiatry because of their widespread use by researchers and clinicians in many Western countries, especially the US. Before LSD was banned, the US National Institutes of Health funded more than 130 studies exploring its clinical utility, with positive results in a range of disorders but particularly anxiety, depression, and alcoholism. However, the displacement of LSD into recreational use and eventual association with the anti-Vietnam war movement led to all psychedelics being banned in the US. This ban became ratified globally under the 1971 UN Convention on narcotics. Since then, research funding, drug production, and the study of psychedelics as clinical agents has been virtually stopped. Until very recently, no companies would manufacture medical-grade psychedelics, which made getting regulatory approval for clinical research—especially clinical trials—very difficult and in some countries (eg, Germany) impossible.

Nutt, D., & Carhart-Harris, R. (2021). The current status of psychedelics in psychiatry. JAMA psychiatry78(2), 121-122.; 10.1001/jamapsychiatry.2020.2171
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Psychedelic Psychiatry’s Brave New World

Abstract

After a legally mandated, decades-long global arrest of research on psychedelic drugs, investigation of psychedelics in the context of psychiatric disorders is yielding exciting results. Outcomes of neuroscience and clinical research into 5-Hydroxytryptamine 2A (5-HT2A) receptor agonists, such as psilocybin, show promise for addressing a range of serious disorders, including depression and addiction.

Nutt, D., Erritzoe, D., & Carhart-Harris, R. (2020). Psychedelic Psychiatry’s Brave New World. Cell181(1), 24-28.
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Therapeutic mechanisms of psilocybin: Changes in amygdala and prefrontal functional connectivity during emotional processing after psilocybin for treatment-resistant depression

Abstract

BACKGROUND:

Psilocybin has shown promise as a treatment for depression but its therapeutic mechanisms are not properly understood. In contrast to the presumed actions of antidepressants, we recently found increased amygdala responsiveness to fearful faces one day after open-label treatment with psilocybin (25 mg) in 19 patients with treatment-resistant depression, which correlated with treatment efficacy.

AIMS:

Aiming to further unravel the therapeutic mechanisms of psilocybin, the present study extends this basic activation analysis. We hypothesised changed amygdala functional connectivity, more precisely decreased amygdala-ventromedial prefrontal cortex functional connectivity, during face processing after treatment with psilocybin.

METHODS:

Psychophysiological interaction analyses were conducted on functional magnetic resonance imaging data from a classic face/emotion perception task, with the bilateral amygdala and ventromedial prefrontal cortex time-series as physiological regressors. Average parameter estimates (beta weights) of significant clusters were correlated with clinical outcomes at one week.

RESULTS:

Results showed decreased ventromedial prefrontal cortex-right amygdala functional connectivity during face processing post- (versus pre-) treatment; this decrease was associated with levels of rumination at one week. This effect was driven by connectivity changes in response to fearful and neutral (but not happy) faces. Independent whole-brain analyses also revealed a post-treatment increase in functional connectivity between the amygdala and ventromedial prefrontal cortex to occipital-parietal cortices during face processing.

CONCLUSION:

These results are consistent with the idea that psilocybin therapy revives emotional responsiveness on a neural and psychological level, which may be a key treatment mechanism for psychedelic therapy. Future larger placebo-controlled studies are needed to examine the replicability of the current findings.

Mertens, L. J., Wall, M. B., Roseman, L., Demetriou, L., Nutt, D. J., & Carhart-Harris, R. L. (2020). Therapeutic mechanisms of psilocybin: Changes in amygdala and prefrontal functional connectivity during emotional processing after psilocybin for treatment-resistant depression. Journal of Psychopharmacology, 10.1177/0269881119895520
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