This open-label study (n=70) compared the effect of esketamine (28-84mg; 8x) in those with bipolar treatment-resistant depression (B-TRD, n=35) and those with unipolar TRD. There was no significant difference between the two groups on depression scores, and both responded to treatment. Those in the B-TRD group had more anxiety-reducing effects. This study is part of the REAL-ESK study.
Bipolar Disorders An International Journal of Psychiatry and Neurosciences
This cell study finds no (negative) effect of classical psychedelics on T cell and monocyte immune responses. This indicates that they can be used by people with life-threatening diseases who are immunocompromised.
This systematic review (2023) finds that oral ketamine (35mg-85mg/70kg) has antidepressive effects, but that the evidence (n=2336, s=22) is still quite limited (only 4 RCTs with a high chance of bias).
This theory-building article (2023) proposes a model of psychotherapeutic processes associated with ayahuasca consumption. It identifies five key effects: somatic effects, introspection and emotional processing, increased self-connection, increased spiritual connection, and gaining of insights and new perspectives.
This theory-building article (2023) proposes that a patient's 'readiness' (eligibility & capacity) is taken into account to optimise the outcomes of psilocybin/psychedelic-assisted therapies (PAT). Factors discussed include intrapersonal (e.g. openness & motivation) and interpersonal (e.g. therapeutic alliance) factors.
This survey study (n=2822) examined the prevalence and associations of challenging, difficult, or distressing experiences using classic psychedelics in a subsample of respondents (n=613) who reported lifetime classic psychedelic use. Of those, 59% indicated no challenging experiences, 9% indicated having a difficult experience lasting more than one day, and 2.6% reported seeking medical/psychiatric/psychological assistance.
This theory-building paper (2023) shows that structure-function coupling (patterns of brain activity) is a generalisable indicator of consciousness. An increase in functional coupling indicates a loss of consciousness (e.g. brain-inured patients or anaesthesia), and opposite changes (decoupling of brain function from structure) are seen under the influence of psychedelics (e.g. LSD or ketamine).
This case series (n=4) reflects on the use of ketamine (35mg/70kg, up to 8x) as an adjunct treatment for psychotic treatment-resistant depression (TRD). It finds that all participants were in remission after treatment and that suicidal ideation went down.
This interview study (n=3) examines menstrual changes after using classical psychedelics. It finds 1) resumption of menstruation, 2) earlier menstruation, and 3) improved menstrual regularity. A possible underlying mechanism is the (in)direct effects of 5-HT2a agonism on the hypothalamic-pituitary-gonadal axis.
This interview study (n=30) investigates the experience of those who attended a psilocybin truffle retreat in The Netherlands. It finds that 30% experienced challenges in integration (e.g. spiritual bypass, lack of support) which also correlated with positive after-effects including long-term remission of significant health conditions.
This naturalistic study (n=18) on microdosing found that it led to a decrease in positive and overall emotional diversity (emodiversity). Participants experienced more "awe, wonder, or amazement" and "ashamed, humiliated, or disgraced" emotions during microdosing days and fewer "joyful, glad, or happy" emotions.
This animal study suggests that activating serotonin 2A receptors is essential for tryptamine-based psychedelics to produce antidepressant-like effects in rodents. The study also suggests that psychedelic tryptamines can induce hallucinogenic and therapeutic effects through activation of the same receptor. It highlights the need for full mechanistic understanding of how these molecules produce therapeutic effects.
This review (2022) proposes a unified neurophenomenological (NP) approach to studying non-ordinary states of consciousness (psychedelics, meditation, hypnosis). By focusing on the experience (phenomenology; e.g. interviews) and combining it with neurophysiological measures, a rich explanatory framework could emerge.
This rat study finds that methylone (5-3-mg/kg) showed a reduction of 95% in immobility in the forced swim test (FST), a measure of antidepressant effects commonly used in mice studies. Methylone is similar to MDMA but shows less activity in the serotonin system. Pretreatment with an antidepressant (fluoxetine) didn't change the effects, indicating they may be co-administrated.
This re-analysis of NSDUH survey data (n=56.000, 6.300 psychedelic users) finds that those who used LSD and psilocybin were more likely to have a substance dependency or abuse, those who used mescaline less likely, both compared to the rest of the survey group. As always, these are mere correlations and non-pharmacological (e.g. socio-economic) factors could explain both the positive and negative correlations.
This pre-print mice study finds that 5-MeO-DMT delayed the onset of REM sleep as measured with EEG, and showed behavioural signals (e.g. head twitches) consistent with psychedelic effects, whilst during the waking stage the EEG measures were also showing signs of REM sleep (paradoxical wakefulness).
This reanalysis of survey data (n=3817) finds that nature-relatedness (NR) is only predicted by past use of psilocybin. As the surveys are observations, the question is still out if the pharmacology or the way people use different psychedelics (setting) is driving this result.
This pre-print re-analysis of an RCT of MDMA-assisted therapy for PTSD finds that study participants (n=90) had significant improvements in the measures of self-experience (e.g. alexithymia - the inability to identify & describe emotions experienced by oneself). The change in scores of self-experience correlate with recovery from PTSD.
This pre-print analysis of population survey data (2015-2019; 280.000 respondents) finds an increase in LSD use (from .06% to 0.9%, +47%). Those who self-reported Hallucinogen Persisting Perception Disorder (HPPD) didn't increase their use. "LSD does not appear to contribute significantly to the country’s public health problems."
This interview study (n=21) presented service members and veterans, who had a history of traumatic brain injury (TBI) with information on psychedelic-assisted therapy (PAT). Before presenting info, they were neutral, after they had significantly more positive views on psychedelic drugs (3.2 out of 5), interest in PAT (3.7), and would support medical PAT (4.3).
This re-analysis of survey data (n=985) finds three different clusters (subtypes) of the psychedelic experience. The subtypes, found with machine learning, were associated with reduced anxiety and depression symptoms and other markers of psychological well-being. The subtypes were also highly reproducible across multiple psychedelic substances.
This theory-building paper (2022) introduces a new model of psychopathology called canalization, which is a form of plasticity that relates to increased model precision. It suggests that TEMP, combined with psychological support, can counter the entrenchment of canalization in pathological phenotypes, and offers suggestions for experiments to test its main hypotheses and implications.
This double-blind placebo-controlled study (n=56) found that one psilocybin-assisted therapy (16mg/70kg, 2 prep + 3 integration meetings) session significantly reduced depressive symptoms (MADRS & BDI) in those suffering from a major depressive disorder (MDD, n=26). Fourteen days after the intervention, 54% of those in the psilocybin group met remission criteria (<10 on MADRS).
This open-label study (n=25) explored the effects of using intravenous ketamine to treat treatment-resistant depression (TRD) in participants over the age of 60. Depressive symptoms improved significantly, 48% of participants responded, and during the acute phase, executive function measures and the fluid cognition composite score improved (Cohen's d = 0.61).
This follow-up study (n=15) used interviews to better understand self-reported psilocybin use among participants with bipolar disorder. Three overarching themes were identified: Mental Health Improvements, Undesired Mental Health Impacts and Salient Contextual Factors for psilocybin use.
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