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Our vision is that psychedelics can be used worldwide to better the lives of as many as 450 million people who suffer from mental health problems. Our information hopes to make that vision come to life just a little faster.
Here will be a narrative, readable, summary of the research.
In our literature study we came across the following studies of note. Browse the meta, review, commentary articles for an overview. Check out the individual studies for specific experiments and observations.
Reflections on the Concord Prison Project and the follow-up study
1998 | Metzner, R.
In this commentary (1998), Ralph Metzner reflects on the erroneous conclusions drawn by him and Timothy Leary from the Concord Prison experiment which had falsely reported lowered the rate of recidivism amongst inmates who had undertaken a psychedelic intervention, despite evidence that most prisoners actually returned for parole violations related to committing new crimes. Metzner concludes that although psychedelics can bring about profound experiences of insight and personality change, criminal behavior patterns take a much more concerted system of rehabilitation and community support to change.
Predicting Reactions to Psychedelic Drugs: A Systematic Review of States and Traits Related to Acute Drug Effects
2021 | Aday, J. S., Bloesch, E. K., Davis, A. K., Davoli, C. C., Mitzkovitz, C. M.
This review (14 studies) found that traits of absorption, openness, acceptance, and surrender correlated with more positive and mystical (MEQ30) experiences. Gender didn't predict drug effects, but possible biomarkers are serotonin receptor binding potential, executive network node diversity, and right anterior cingulate cortex volume.
Lifetime use of psychedelics is associated with better mental health indicators during the COVID-19 pandemic
2021| Cavanna, F., Cuiule, J., Di Tella, R., González, P., Milano, V., Pallavicini, C., Tagliazucchi, E.
This survey (n=5618) found that those who used psychedelics (32% of the sample) had increased positive affect and more resilient personality traits (e.g. plasticity) during the COVID-19 pandemic.
The psychology of philosophy: Associating philosophical views with psychological traits in professional philosophers
2021| Anderson, D., Yaden, D. B.
This survey study (n=314) investigated professional philosophers' worldviews in relation to psychological traits, such as personality, well-being, lifestyle, transformative life experiences, and psychedelic use. Amongst other results, they found an association between Hard Determinism (no free will) and more depression - as well as lower life satisfaction, and that psychedelics use was associated with non-realist/subjective view of moral and aesthetic value judgments, while transformative or self-transcendent experiences predicted theism and idealism as their worldview.
Clinical Studies of Lysergic Acid Diethylamide
1986| Anderson, E. W., Rawnsley, K.
This early clinical study (1954) investigated the dose-range effects of LSD (10-600μg) administered to patients and clinical staff (n=23) across 54 different research sessions and found that its effects entail highly potent perceptual alterations that are sensitive to the environment and variable across different individuals. They also note the emergence of phenomena such as enhanced sexual arousal and ego-dissolution and highlight its utility at illuminating basic personality structures but remain inconclusive as to whether it has therapeutic benefit in response to continued administration.
Mental changes experimentally produced by d-lysergic acid diethylamide tartrate
1988| Deshon, H. J., Rinkel. M., Solomon, H. C.
This early open-label investigation (1952) reports observations of mental changes in normal adults (n=15) produced by LSD (70μg/70kg) across 17 repeated experiments. Alterations were observed in the areas of thinking and speech, emotion, mood and affect, sensory and time perception, behavior, morbid ideas, and sensory experiences, and neurological signs, which were taken to reflect a schizophrenic-like state.
LSD-induced entropic brain activity predicts subsequent personality change
2016| Carhart-Harris, R. L., Feilding, A., Kaelen, M., Lebedev, A. V., Lövdén, M., Nilsson, J., Nutt, D. J.
This counterbalanced, placebo‐controlled within-subjects study (n=20) investigated whether the combination of administering LSD (75µg/70kg) while listening to music can induce changes in entropic brain activity during resting state, and cause subsequent changes in personality structure. Results indicated that acute increases in brain entropy affecting the disintegration of functional connectivity within sensory and higher-order networks were predictive of subsequent increases in trait openness measured 2 weeks later, and this relationship was enhanced by listening to music.
Psychological and neuropsychological assessment of regular hoasca users
2016| Areco, K., Barbosa, P., Bogenschutz, M. P., da Silveira, D. X., Hoy, R., Pommy, J. A., Strassman, R. J., Thoma, R.
This study (n=57) assessed the socio-economic status, mood, personality traits, impulsiveness, drug use, quality of life, extrinsic and intrinsic religiosity, and neuropsychological function of ayahuasca users and non-users. The findings indicate that religious use of ayahuasca does not adversely affect neuropsychological functioning and may have positive effects on substance abuse and mood.
Exploring the relationship between microdosing, personality and emotional insight: A prospective study
2021| Bright, S. J., Dressler, H. M., Polito, V.
This prospective survey study (n=24) explored the relationship between microdosing, personality change, and emotional awareness. Conscientiousness increased, while neuroticism decreased across these time points and correlated negatively with duration of prior microdosing experience. Extraversion correlated positively with both duration of prior microdosing experience and lifetime number of microdoses.
Prediction of MDMA response in healthy humans: a pooled analysis of placebo-controlled studies
2021| Harder, S., Ley, L., Liechti, M. E., Studerus, E., Vizeli, P.
This pooled-data analysis (n=194) of healthy participants of RCTs with MDMA (75mg-125mg) found that MDMA plasma concentration was the strongest predictor of outcomes. The more active the CYP2D6 enzyme, the lower the plasma concentration. And the higher the score on Openness, the more closeness and two subscales of an altered states of consciousness questionnaire (5D-ASC).
Examining changes in personality following shamanic ceremonial use of ayahuasca
2021| Campbell, W. K., Carter, N. T., Miller, J. D., Weiss, B.
This open-label study (n=256) found that directly after an ayahuasca retreat, and three months later, the personality of the participants was changed. The strongest finding was for neuroticism, but noted should be that there was no control group.
Self-blinding citizen science to explore psychedelic microdosing
2021| Blemings, A., Carhart-Harris, R. L., Erritzoe, D., Feilding, A., Kartner, L., Nutt, D. J., Rosas, F. E., Szigeti, B.
This self-blinding experiment (n=191) finds that the placebo and microdosing groups both experienced similar improvements in self-rated psychological well-being and cognitive function (e.g. mood, energy, creativity) after four weeks. This study provides more evidence that microdosing benefits can be attributed to expectancy (placebo) effects.
Prosocial effects of MDMA: A measure of generosity
2015| de Wit, H., Delton, A. W., Kirkpatrick, M. G., Robertson, T. E.
This placebo-controlled within-subjects study (n=32) investigated the dose-dependent effects of MDMA (35-70mg/70kg) on generosity, as measured by their willingness to trade-off personal welfare in favor of the welfare of someone else. The higher dose of MDMA increased generosity in relation to a close friend but not a stranger, whereas the lower dose did not affect generosity toward the friend but slightly increased generosity toward a stranger. These results are in line with the prosocial effects of oxytocin, which promotes trust amongst members of a social ingroup but not the out-group.
Recreational use of psychedelics is associated with elevated personality trait openness: Exploration of associations with brain serotonin markers
2019| Carhart-Harris, R. L., Erritzoe, D., Fisher, P. M., Frokjaer, V. G., Knudsen, G. M., Smith, J. M.
This cross-sectional study (n=45) evaluates associations between recreational use of psychedelics and MDMA and (a) personality measures and (b) key markers of cerebral serotonergic signaling (serotonin transporter and serotonin-2A-receptor binding).
Neuroticism is associated with challenging experiences with psilocybin mushrooms
2017| Barrett, F. S., Griffiths, R. R., Johnson, M. W.
This survey study (n=2,974) found that neurotic individuals may be more likely to have a challenging experience with psilocybin.
Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study
2012| Alcázar, M. A., Araújo, D. B., Barbanoj, M. J., Barbosa, P., Bouso, J. C., Cutchet, M., Fábregas, J. M., Fernández, X., Fondevila, S., González, D., Riba, J.
This longitudinal field study (n=242) assessed personality, mental health, life attitudes, and neuropsychological performance in a large number of long-term ritual ayahuasca users and control participants that were matched for age, sex, educational level, and religious background. Long-term ayahuasca use indicated a lower presence of psychopathological symptoms, better performance in neuropsychological tests, higher degrees of spirituality, and better psychosocial adaptation as reflected by some attitudinal traits such as Purpose in Life and Subjective Well-Being, and benefits on mental health were still observable in a one-year follow-up.
Effects of psilocybin therapy on personality structure
2018| Carhart-Harris, R. L., Erritzoe, D., Kaelen, M., MacLean, K. A., Nour, M. R., Nutt, D. J., Roseman, L.
This open-label study (n=20) found that dosages of psilocybin (10, 25mg) in a supportive setting, for those with treatment-resistant depression (TRD), changed their personality. At 3-month follow-up, Neuroticism was decreased, Extraversion and Openness were increased. The changes were similar (but more pronounced) to changes after conventional antidepressant treatment.
Increased nature relatedness and decreased authoritarian political views after psilocybin for treatment-resistant depression
2018| Carhart-Harris, R. L., Lyons, T.
A pilot study (n=14) on how psychedelics increase nature relatedness and decrease authoritarianism. Although the active participants (n=7, with treatment-resistant depression) increased on both, their final scores on those measures were very similar to that of the non-treated (non-depressed) group.
This section compares the research with psychedelics to other therapies, medicines, or treatments.
This section highlights the various measures used and their use in research.
Who are the top researches in this area, the ones who have done the groundbreaking research.
What do we not know at this time? Where are the gaps in our knowledge and are we closing it?
The companies that are actively engaged in researching this topic or (planning to) provide therapy focussed on this topic.
This section highlights everything done outside of academia, from popular press to books and non academic research.