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January 25, 2022
Joseph T. la Torre, Mehdi Mahammadli, Kyle T. Greenway et al.
18 citations
Experts agree that excluding people with personal or familial histories of psychotic symptoms from psychedelic-assisted psychotherapy may be justified only when protocols provide insufficient psychological support. With highly supportive therapy, such treatment is not necessarily contraindicated and may benefit individuals experiencing psychotic symptoms. Key factors for predicting outcomes include specific symptoms, illness duration, severity, therapeutic alliance quality, trauma's role, and the client's social supports.
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March 8, 2022
Gabriella Smedfors, Elliot J. Glotfelty, Negar Kalani et al.
8 citations
Psilocybin, a psychedelic substance approaching clinical use, enhances structural plasticity in the brain. In cultured mouse hippocampal neurons, robust effects on pre- and postsynaptic protein expression (Piccolo and Homer1) appeared 1–3 hours after treatment, while presynaptic Synapsin-1 peaked at 72 hours, suggesting a rapidly normalizing window of plasticity. In an immortalized microglia cell line, psilocybin demonstrated anti-inflammatory effects against a lipopolysaccharide challenge by reducing tumor necrosis factor-alpha secretion. These discrete, acute cell-type-specific effects provide insight into psilocybin's mechanisms of action and potential therapeutic value for conditions like depression and cluster headache.
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November 30, 2020
Brandon Weiss, Joshua Miller, Nathan Carter et al.
7 citations
A longitudinal study of 256 participants at three ayahuasca healing centers in South and Central America found that ceremonial ayahuasca use was associated with a large reduction in Neuroticism, a key personality trait linked to emotional stability. This change was observed both in self-reports (effect size d = 1.00 from baseline to post-use, d = 0.85 at three-month follow-up) and in reports from informants (d = 0.62 at follow-up). The degree of personality change was moderated by participants' baseline personality, acute experiences during the ceremony, and purgative experiences. The findings suggest ayahuasca ceremonies may contribute to lasting personality change, particularly in reducing Neuroticism.
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February 23, 2024
Ari Brouwer, Joshua K. Brown, Earth Erowid et al.
5 citations
Psychedelic therapy may work partly because its temporal structure mirrors the narrative arc of the Hero's Journey. A qualitative analysis of self-reported onset (comeup) and offset (comedown) phases of psilocybin experiences found that the comeup is more often characterized by negatively valenced feeling states, while the comedown is more often characterized by positively valenced feeling states resembling recovery from illness or adversity. This trajectory suggests that initially distressing altered states can ultimately resolve distress, offering a framework for understanding the therapeutic benefits of psychedelics.
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July 7, 2023
Rika Takaba, Daisuke Ibi, Keisuke Yoshida et al.
4 citations
Serotonergic psychedelics like psilocin, DOI, and TCB-2 produce antidepressant-like effects in mice by activating the serotonin 5-HT2A receptor. Mice given a single injection of these drugs showed less immobility in the forced swimming and tail-suspension tests 24 hours later, effects blocked by a 5-HT2A antagonist. The antidepressant-like effect of psilocin lasted at least three weeks. However, only psilocin reduced anxiety-like behavior in the novelty-suppressed feeding test, and this effect was not blocked by the 5-HT2A antagonist. The drugs did not alter spontaneous movement or head-twitch responses. The findings indicate 5-HT2A mediates antidepressant but not anxiolytic effects of these psychedelics.
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March 21, 2022
Maddie Palmer, Olivia Maynard
4 citations
People who use psychedelics recreationally employ more harm reduction practices as they gain experience, and these practices are linked to more positive and less challenging experiences. In a mixed-methods study of 163 participants, greater use of harm reduction strategies was associated with higher scores on the Emotional Breakthrough Inventory and lower scores on the Challenging Experience Questionnaire, especially for first-time use. Commonly reported practices include ensuring good 'set and setting' and attending to the specific drug being taken. Users largely described positive experiences and emphasized the importance of preparation and environment.
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November 14, 2023
Félix Schoeller, Abhinandan Jain, Vladimir Adrien et al.
2 citations
Aesthetic chills—shivers or goosebumps from music, film, or art—may help shift deep-seated negative self-beliefs in people with depression. In a study of 96 patients with major depressive disorder, those exposed to a validated set of chill-inducing multimedia showed positive changes in core schemas, as measured by the Young Schema Questionnaire, and reported emotional breakthroughs similar to altered states from psychedelic substances like psilocybin. The findings suggest that the biological processes behind aesthetic chills could be developed into a non-pharmacological intervention for depression, though more research is needed on the underlying neurophysiology and on safety and effectiveness.
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July 27, 2023
Claire Finkelstein, Olivia Soha, Alana Roy et al.
2 citations
Body Image Disturbance (BID) often persists after physical recovery from anorexia nervosa (AN) because treatments focus on thoughts and behaviors rather than perception and emotion. Psilocybin-assisted psychotherapy (PAP) may address these overlooked symptoms. A panel of six women with lived or living experience of AN and BID reviewed a proposed PAP protocol and provided feedback. Reflexive thematic analysis revealed three themes: enduring uncertainty, managing internal experience, and ambivalence in recovery. The panel also suggested strategies such as graduated interventions, including nominated supports, and comprehensive psychoeducation. Their input directly adapted the treatment manual, resulting in a co-designed PAP manual for BID in AN.
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July 18, 2023
Sanah Malomile Nkadimeng, L. Hay, Christiaan Ml Steinmann et al.
1 citation
Four species of psilocybin-containing mushrooms—Panaeolus cyanescens, Psilocybe natalensis, Psilocybe cubensis, and a leucistic A+ strain of Psilocybe cubensis—were tested in anesthetized Wistar rats for their effects on heart function, serotonin, and nitric oxide (NO) pathways. Hot-water extracts of the mushrooms (5 mg/kg) caused a non-significant increase in left ventricular (LV) parameters after 20 minutes, unlike the immediate effect of the control drug LNAME. The mushrooms significantly raised serotonin levels and suppressed endothelial nitric oxide synthase (eNOS) activity both in vivo and in vitro on H9C2 cardiomyocytes. The findings suggest that disruption of eNOS pathways may underlie temporary blood pressure increases from psilocybin mushrooms, with different species producing distinct cardiac effects.
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January 4, 2024
Laetitia Vanderijst, Felix Hever, Anne Buot et al.
A proposed double-blind, randomized, placebo-controlled phase II trial will test whether adding psilocybin-assisted therapy to a 4-week inpatient rehabilitation program for severe alcohol use disorder is feasible and clinically effective. Sixty-two participants aged 21–64 years will receive either a high dose (30 mg) or an active placebo dose (5 mg) of psilocybin, both paired with a brief acceptance and commitment therapy intervention. The primary clinical outcome is the change in percentage of heavy drinking days from baseline to four weeks after hospital discharge. Secondary outcomes include drinking behavior up to six months, symptoms of depression and anxiety, neuroplasticity, and changes in neurocognitive systems linked to addiction.
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August 23, 2023
Lucas Villar Magalhães da Cruz, Bheatrix Bienemann Favero, Fernanda Palhano-Fontes et al.
First-time ayahuasca users with treatment-resistant depression and healthy controls described their subjective experiences in open-ended questions. Textual analysis of responses from nine depressed and 20 healthy individuals revealed five clusters: altered consciousness, cognitive changes, somatic alterations, auditory experiences, and visual perceptual content. Depressed participants reported more aversive bodily reactions, suggesting specific experiential features in depression. The results align with prior psychedelic research and may guide therapeutic applications of ayahuasca.
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May 12, 2023
Gabriel Thorens, Louise Penzenstadler, Leonice Furtado et al.
A patient with generalized anxiety disorder and claustrophobia who had not improved with conventional therapy underwent three sessions of psilocybin-assisted psychotherapy that included both imaginary and real exposure to an elevator. After treatment, anxiety and fear of closed spaces, elevators, and planes decreased. Scores on the Beck Depression Inventory-II, State-Trait Anxiety Inventory, and Fear Questionnaire showed significant improvement. The patient reported feeling more relaxed, more willing to face fearful situations, and a shift in perception of fearful stimuli, possibly reflecting new memory representations and a disconfirmatory experience.
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Adam Włodarczyk, Wiesław J. Cubała, Maria Węgielnik-gałuszko et al.
In hospitalized patients with treatment-resistant depression (major depressive or bipolar disorder), intravenous ketamine treatment was associated with changes in psychotic symptoms over time among those with epilepsy, but not among those with other somatic conditions. The study, which included 49 participants and was limited by a small, unblinded, single-site design, suggests that careful monitoring for psychotic symptoms is needed when using ketamine in patients with epilepsy, and that somatic comorbidities may influence dissociative side effects.