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Journal of Psychopharmacology

ISSN 0269-8811

266 papers in the library · 27,424 citations · publishing 1998-2026

Papers

Psilocybin use is associated with lowered odds of crime arrests in US adults: A replication and extension

Journal of Psychopharmacology January 1, 2022 Grant M Jones, Matthew K Nock 30 citations

Lifetime use of psilocybin was linked to lower odds of arrest for seven of eleven crime categories, with adjusted odds ratios ranging from 0.30 to 0.73. Peyote use was associated with reduced odds of motor vehicle theft (aOR = 0.30) and driving under the influence (aOR = 0.52), while mescaline use was associated with reduced odds of drug possession or sale (aOR = 0.51). Most other substances showed no relationship or were linked to higher odds of arrest. The findings suggest classic psychedelic substances may be associated with lowered criminal behavior, but further research is needed to explore causal or third-variable explanations.

Psilocybin’s effects on cognition and creativity: A scoping review

Journal of Psychopharmacology July 1, 2023 Justin N Bonnieux, Baeleigh VanderZwaag, Zahra Premji et al. 29 citations

A scoping review of 42 studies on psilocybin's effects on cognition and creativity in adults found that macrodoses tended to impair cognitive performance and creativity during the acute phase (minutes to hours after intake), while microdoses tended toward creative enhancement. The few macrodosing studies that included post-acute measures (1–85 days) reported primarily null but some positive effects. Psilocybin was mostly administered orally (83%) in bodyweight-adjusted doses (74%) to healthy participants (90%). Only 26% of studies explicitly reported safety outcomes, and among those, only one reported serious adverse reactions. The findings are limited by methodological concerns and inadequate assessment of long-term effects.

MDMA-assisted therapy for posttraumatic stress disorder: A pooled analysis of ethnoracial differences in efficacy and safety from two Phase 2 open-label lead-in trials and a Phase 3 randomized, blinded placebo-controlled trial

Journal of Psychopharmacology June 21, 2022 T. Ching, Monnica T. Williams, Julie B. Wang et al. 29 citations

In a pooled analysis of two Phase 2 open-label trials and one Phase 3 randomized placebo-controlled trial of MDMA-assisted therapy for PTSD, no significant difference in symptom reduction was found between BIPOC and non-Hispanic White participants who received MDMA. Among those given placebo-assisted therapy, BIPOC participants showed a trend toward greater improvement than non-Hispanic Whites. Non-Hispanic Whites had significantly larger reductions in PTSD symptoms with MDMA than with placebo, but no such treatment difference emerged among BIPOC participants. Adverse events were mostly mild or moderate across all groups. The findings suggest MDMA-assisted therapy is effective and safe across ethnoracial groups, though subgroup sizes were imbalanced.

Race and ethnicity moderate the associations between lifetime psychedelic use (MDMA/ecstasy and psilocybin) and major depressive episodes

Journal of Psychopharmacology October 31, 2022 Grant M Jones 28 citations

Race and ethnicity influence how naturalistic use of MDMA/ecstasy and psilocybin relates to major depressive episodes. Among White adults, use of either substance was linked to lower odds of lifetime, past year, and past year severe major depressive episodes. For Hispanic adults, use of either substance was associated with lower odds only for a past year major depressive episode. For non-Hispanic racial minority adults, neither MDMA/ecstasy nor psilocybin use was associated with lower odds of any depressive outcome. The findings suggest that the potential mental health benefits of these psychedelics may not be uniform across racial and ethnic groups.

Effects of ecstasy on cooperative behaviour and perception of trustworthiness: A naturalistic study

Journal of Psychopharmacology August 13, 2014 LH Stewart, B. Ferguson, CJA Morgan et al. 28 citations

Acute recreational use of MDMA (ecstasy) increases perceived trustworthiness of faces and cooperative behavior in economic games. In a study comparing 17 ecstasy users tested on the night of drug use and again three days later with 22 controls, users rated faces as more trustworthy and showed more cooperation on dictator and ultimatum games while intoxicated. By day three, no group differences remained on these tasks. Self-ratings showed typical acute effects such as euphoria and energy, with negative effects like reduced empathy and increased distrust emerging on day three. The findings suggest a single dose enhances aspects of empathy, which may contribute to its recreational popularity and potential therapeutic use.

Parallel changes in serotonin levels in brain and blood following acute administration of MDMA

Journal of Psychopharmacology October 10, 2012 Cheryl M Collins, Joris Kloek, J.m. Elliott 28 citations

In rats, MDMA (20 mg/kg) caused a parallel drop in serotonin levels in the frontal cortex and blood, with decreases of 63% and 46% respectively at 2 hours, partial recovery by 8 hours (42% and 38% below control), and further recovery by 18 hours (19% and 24% below control). A tryptophan supplement (82.5 mg/kg) raised serotonin in both brain (39%) and blood (26%) in naïve rats, but after MDMA, the same supplement raised brain serotonin only 26% and had no effect on blood serotonin. Blood serotonin appears to be a useful marker for brain serotonin levels after acute MDMA, suggesting platelet serotonin could serve similarly in human studies.

Memory and mood during the night and in the morning after repeated evening doses of MDMA

Journal of Psychopharmacology February 28, 2008 KPC Kuypers, M. Wingen, Jg Ramaekers 28 citations

Memory performance worsens progressively overnight due to sleep loss, and taking MDMA (ecstasy) in the evening adds to that impairment. In a double-blind, placebo-controlled crossover study with 14 healthy adults, MDMA (75 mg and 50 mg split over the evening) caused additional deficits in verbal and spatial memory beyond those from sleep deprivation alone. During the night, MDMA improved response speed and increased feelings of vigor, friendliness, elation, anxiety, confusion, arousal, and positive mood, but these effects returned to placebo-like levels by morning. Evening MDMA selectively impairs memory, and this harm is separate from and adds to the memory impairment caused by sleep deprivation.

Effects of different subanaesthetic doses of (S)-ketamine on psychopathology and binocular depth inversion in man

Journal of Psychopharmacology January 1, 2003 Torsten Passie, Matthias Karst, Mathias Borsutzky et al. 27 citations

The NMDA neurotransmitter system's role in psychoses is not fully understood, but NMDA antagonists like phencyclidine and ketamine induce psychotic states similar to schizophrenia. Binocular depth inversion, a visual illusion impaired in psychotic states, was tested in 12 healthy male volunteers using stereoscopic pictures of natural and artificial objects. Two subanaesthetic doses of the psychotomimetic S-enantiomer of ketamine were compared with placebo. Despite dose-dependent subjective and objective psychopathology, no significant impairment of binocular depth perception occurred with (S)-ketamine. The findings suggest implications for memory, perception formation, and bottom-up processing in ketamine model psychosis and schizophrenia.

Effects of discontinuation of serotonergic antidepressants prior to psilocybin therapy versus escitalopram for major depression

Journal of Psychopharmacology March 22, 2024 Tommaso Barba, David Erritzøe, Meg J. Spriggs et al. 26 citations

In a clinical trial comparing psilocybin plus psychological support to escitalopram plus psychological support for major depressive disorder, patients who discontinued their SSRI or SNRI medication before receiving psilocybin showed a reduced treatment effect on all depression severity and well-being measures compared with those who were unmedicated at trial entry. Discontinuation did not affect the intensity of the acute psychedelic experience. The findings are exploratory and hypothesis-generating, not confirmatory, and the study did not test SSRI/SNRI continuation. A controlled trial comparing discontinuation versus continuation before psilocybin is needed.

Neurocognitive performance following acute mephedrone administration, with and without alcohol

Journal of Psychopharmacology August 25, 2016 EB de Sousa Fernandes Perna, Esther Papaseit, Clara Pérez‐mañá et al. 26 citations

Mephedrone, a recreational drug similar to MDMA, impairs short-term spatial memory one hour after intake but improves critical tracking performance four hours later. When combined with alcohol, mephedrone reduces reaction time compared to alcohol alone, but does not counteract alcohol's impairing effects on divided attention or spatial memory. Alcohol alone impairs both short- and long-term spatial memory and divided attention. The findings suggest mephedrone enhances psychomotor performance while harming memory, and its stimulatory effects are insufficient to offset alcohol-induced deficits on most cognitive tasks.

Cannabis-induced altered states of consciousness are associated with specific dynamic brain connectivity states

Journal of Psychopharmacology June 3, 2019 Yuliya Zaytseva, Jiřı́ Horáček, Jaroslav Hlinka et al. 25 citations

Delta-9-tetrahydrocannabinol, the active compound in cannabis, temporarily alters how brain regions communicate with each other. In 19 occasional cannabis users who underwent two resting-state fMRI scans—one shortly after smoking a cannabis cigarette and one after at least a week without cannabis—a transient connectivity state appeared only during intoxication. This state showed high connectivity within and between auditory and somato-motor cortices, along with anti-correlation with subcortical structures and the cerebellum. Subjective perceptual changes and THC plasma levels were linked to this state, suggesting a neural biomarker of cannabis intoxication.

Comparison of the behavioral effects of mescaline analogs using the head twitch response in mice

Journal of Psychopharmacology February 21, 2019 Adam L. Halberstadt, Muhammad Chatha, Stephen J. Chapman et al. 25 citations

In mice, the hallucinogenic compound mescaline and several of its chemical analogs produce a distinctive head-twitch response that depends on activation of the 5-HT2A receptor. Adding a methyl group to mescaline (making TMA) doubled its potency, and replacing the 4-methoxy group with larger ethoxy or propoxy groups also increased potency for both mescaline and TMA. However, for a different set of isomers (TMA-2 and its analogs), changing the 4-alkoxy group did not alter potency, even though TMA-2 itself was twice as potent as mescaline. These potency patterns in mice closely match known human hallucinogenic data and show that different substitution patterns on the phenyl ring produce distinct structure-activity relationships.

A critical evaluation of QIDS-SR-16 using data from a trial of psilocybin therapy versus escitalopram treatment for depression

Journal of Psychopharmacology April 25, 2023 Brandon Weiss, David Erritzøe, Bruna Giribaldi et al. 24 citations

A reanalysis of data from a trial comparing psilocybin therapy (PT) to escitalopram (ET) for major depressive disorder found that 14 of 16 outcome measures favored PT, but the QIDS-SR-16 did not. The QIDS-SR-16 showed higher variance, imprecision from compound items and sum-scoring, vague response options, and lack of focus on a core depression factor. When the trial data were examined at item, facet, and factor levels, results suggested PT was superior in reducing depressed mood, anhedonia, a core depression factor, and specific symptoms like sexual dysfunction. This raises concerns about relying on individual scales that miss depression's multidimensional structure.

MDMA affects both error-rate dependent and independent aspects of decision-making in a two-choice prediction task

Journal of Psychopharmacology June 27, 2005 Franz X. Vollenweider, Matthias E. Liechti, Martin P. Paulus 24 citations

MDMA alters decision-making in a way that depends on the degree of success or failure. In a crossover trial with 42 healthy volunteers, a single 1.5 mg/kg oral dose of MDMA increased how much previous responses and stimuli influenced current choices, particularly when error rates were low (20% and 50%). The drug did not significantly change basic response characteristics like response latency or switching, and participants' self-assessed psychological states did not predict the decision-making patterns. These results suggest that acute MDMA affects success-related response selection during decision-making.

Therapeutic (Sub)stance: Current practice and therapeutic conduct in preparatory sessions in substance-assisted psychotherapy—A systematized review

Journal of Psychopharmacology October 20, 2022 Sascha B Thal, Michelle Wieberneit, Jason M Sharbanee et al. 23 citations

A systematized review of 83 sources found consensus that adequate preparation before substance-assisted psychotherapy (SAPT) sessions is important for safety and therapeutic effect. Preparatory practices include screening participants, optimizing set and setting, and preparing therapists with appropriate competencies and roles. However, the extent and specific approaches vary across models, and more rigorous qualitative and quantitative research is needed to determine optimal preparation techniques.

Safety, tolerability, pharmacokinetics, and subjective effects of 50, 75, and 100 µg LSD in healthy participants within a novel intervention paradigm: A proof-of-concept study

Journal of Psychopharmacology March 1, 2022 Neiloufar Family, Peter S. Hendricks, Luke T. J. Williams et al. 23 citations

LSD doses of 50, 75, and 100 micrograms are tolerable and safe in healthy adults when administered in a novel group-based intervention paradigm with one attendant per participant. Thirty-two adults (mean age 28.8 years) received LSD or placebo across open-label and double-blind designs. No serious adverse events occurred; 28% of participants reported at least one mild expected adverse event and one moderate event. Peak blood plasma levels appeared 1.2 to 2 hours after administration, with an apparent half-life of 2.8 to 4.3 hours. LSD produced greater subjective effects than placebo, including mystical-type experiences. Further research is needed in clinical populations.

The acute effects of cannabidiol on the neural correlates of reward anticipation and feedback in healthy volunteers

Journal of Psychopharmacology August 5, 2020 Will Lawn, J. P. Hill, Chandni Hindocha et al. 23 citations

A single 600 mg oral dose of cannabidiol did not alter brain activity related to anticipating or receiving rewards in healthy adults. Using functional magnetic resonance imaging during a monetary incentive delay task, the expected reward-related brain regions—including the insula, caudate, nucleus accumbens, anterior cingulate, and orbitofrontal cortex—were activated, but no difference was observed between cannabidiol and placebo. Bayesian analyses confirmed that activity in these regions was similar under both conditions, and behavioral measures of motivation for reward also showed no significant difference. The findings suggest that acute cannabidiol does not affect the neural correlates of reward anticipation or feedback in healthy individuals.

Temporal dynamics of the pharmacological MRI response to subanaesthetic ketamine in healthy volunteers: A simultaneous EEG/fMRI study

Journal of Psychopharmacology January 21, 2019 Rebecca McMillan, Anna Forsyth, Doug Campbell et al. 23 citations

Ketamine infusion in healthy men increases blood-oxygen-level dependent signals across the cortex and decreases them in the subgenual anterior cingulate cortex, but the decrease is largely due to physiological noise, especially cardiac pulsatility, rather than neural activity. Modeling the pharmacological MRI response with a single time course misses the full range of neural dynamics; using simultaneously recorded electroencephalography power time series reveals distinct temporal responses to ketamine, though no EEG band correlated with the subgenual anterior cingulate cortex decrease.

Psychedelic symptoms of cannabis and cocaine use as a function of trait impulsivity

Journal of Psychopharmacology January 8, 2015 JHP van Wel, DB Spronk, Kim P. C. Kuypers et al. 23 citations

Regular drug users with normal or high trait impulsivity levels showed largely similar subjective responses to cocaine, cannabis, and placebo. Cannabis increased dissociation, psychedelic symptoms, fatigue, confusion, depression, and anxiety while decreasing arousal, positive mood, vigor, friendliness, and elation. Cocaine increased dissociation, psychedelic symptoms, vigor, friendliness, elation, positive mood, anxiety, and arousal while decreasing fatigue. Only a few subjective measures differed by impulsivity level; psychedelic symptoms were most intense in high-impulsivity subjects. Trait impulsivity correlated negatively with vigor (r = -.197) and positively with loss of thought control (r = .237) during cannabis intoxication, but a broad association between trait impulsivity and psychedelic drug experience was absent.

Older adults in psychedelic-assisted therapy trials: A systematic review

Journal of Psychopharmacology January 1, 2024 Lisa Bouchet, Zachary Sager, Antoine Yrondi et al. 22 citations

Older adults (65+) account for less than 1.4% of participants in psychedelic clinical trials, despite these compounds showing potential for conditions common in this age group, such as depression, anxiety, and existential distress. A systematic review of 36 trials involving 1,400 patients found only 19 were aged 65 or older. Safety data for 10 of these older adults showed no serious adverse events; only transient mild-to-moderate effects like anxiety, gastrointestinal upset, and hypertension occurred during dosing sessions. The authors conclude that psychedelic-assisted psychotherapy appears safe and well tolerated in older adults and warrants more rigorous investigation for psychiatric treatment in this population.

The revival of the psychedelic experience scale: Revealing its extended-mystical, visual, and distressing experiential spectrum with LSD and psilocybin studies

Journal of Psychopharmacology October 31, 2023 Kurt Stocker, Matthias Hartmann, Laura Ley et al. 22 citations

A questionnaire that measures psychedelic experiences, the Psychedelic Experience Scale (PES), contains more useful subscales than the well-known Mystical Experience Questionnaire (MEQ30). Analyzing 239 measurements from 140 healthy participants given LSD or psilocybin, researchers identified four additional factors beyond the original four: paradoxicality, connectedness, visual experience, and distressing experience. Paradoxicality and connectedness correlated strongly with the mystical subscale. Adding these new subscales to the MEQ30 increased the variance explained alongside another measure, the 5D-ASC. A cluster analysis supported these findings. The results provide a validated 6-factor structure (MEQ40) covering mystical experience more comprehensively and a broader 48-item version (PES48), with the full 100-item PES available for future research.

Greater empathy in MDMA users

Journal of Psychopharmacology February 5, 2019 Molly Carlyle, Tobias Stevens, Leah Fawaz et al. 22 citations

People who use MDMA (ecstasy) recreationally over the long term show normal or even enhanced empathy compared to other drug users. In a study of 67 individuals, those who used MDMA scored higher on self-reported emotional empathy and on a computer task measuring cognitive empathy than poly-drug users who did not use MDMA. However, MDMA users did not differ from other groups in how they subjectively reacted to social exclusion. The amount or frequency of MDMA use was not linked to empathy levels. These findings suggest that moderate, long-term recreational MDMA use does not cause heightened social distress and may be associated with better empathy, supporting the drug's safety profile for potential therapeutic use.

Individual and combined effects of cannabidiol and Δ 9 -tetrahydrocannabinol on striato-cortical connectivity in the human brain

Journal of Psychopharmacology May 20, 2022 Matthew B. Wall, Tom P. Freeman, Chandni Hindocha et al. 21 citations

THC strongly disrupts connectivity between the striatum and cortex, but co-administering CBD mitigates this effect in the limbic striatum network. In one study, inhaled cannabis with 8 mg THC or 8 mg THC plus 10 mg CBD disrupted associative and sensorimotor networks, while THC alone also disrupted the limbic striatum network. In a second study, oral 600 mg CBD increased connectivity in the associative network and caused minor disruptions in limbic and sensorimotor networks. The insula emerges as a key region affected by cannabinoid-induced changes in functional connectivity, with implications for understanding cannabis-related disorders and developing cannabinoid therapeutics.

Therapeutic uses of psychedelics for eating disorders and body dysmorphic disorder

Journal of Psychopharmacology December 14, 2022 Nicole Ledwos, Justyne D. Rodas, Muhammad Ishrat Husain et al. 20 citations

A systematic review of five studies (two exploratory studies, two case reports, and one prospective study) found limited evidence on the therapeutic potential of psychedelics for body dysmorphic disorder and eating disorders. Effects on symptoms were identified mostly through thematic analyses and self-reports. The review concludes that more research is needed to determine the safety and efficacy of psychedelics in these conditions and suggests avenues for future exploration.

Effect of ketamine dose on self-rated dissociation in patients with treatment refractory anxiety disorders

Journal of Psychopharmacology October 1, 2017 Cameron Castle, Andrew Gray, Shona Neehoff et al. 20 citations

Ketamine produces dose-dependent dissociative symptoms in patients with treatment-resistant anxiety, while midazolam does not. The Clinician-Administered Dissociative States Scale (CADSS) shows high internal consistency (Cronbach alpha = 0.937) for measuring these symptoms, though it does not capture thought disorder. Individual items varied in their sensitivity to ketamine dose and magnitude of change. Removing items did not meaningfully improve the scale's reliability, and acceptable consistency remained even after excluding items unresponsive at lower doses. The CADSS is an internally consistent tool for assessing ketamine-induced dissociation in clinical trials for anxiety.