International journal of environmental research and public health
December 16, 2019
Hannes Kettner, Sam Gandy, Eline C H M Haijen et al.
159 citations
People who use psychedelics report a stronger sense of connection to nature, and this increase lasts for at least two years. In a prospective online study, individuals planning to use a psychedelic completed questionnaires before and after their experience. Nature relatedness was significantly higher at 2 weeks, 4 weeks, and 2 years after the experience. The increase was linked to greater psychological well-being and depended on how strongly participants felt ego-dissolution and how much they perceived their natural surroundings during the acute psychedelic state. The findings suggest a causal, context-dependent effect of psychedelic use on nature relatedness, with implications for mental health treatments and planetary health.
JAMA psychiatry
June 1, 2025
Lorenz Mueller, Joyce Santos de Jesus, Yasmin Schmid et al.
14 citations
Repeated low doses of LSD (20 μg twice weekly for six weeks) did not reduce ADHD symptoms more than placebo in adults with moderate-to-severe ADHD. In a double-blind randomized trial with 53 participants, the LSD group showed an average 7.1-point improvement on the ADHD symptom scale, while the placebo group improved by 8.9 points—a difference that was not statistically significant. The treatment was physically safe and psychologically well tolerated. The findings suggest that microdosing LSD, despite popular interest, offers no advantage over placebo for ADHD symptom relief.
International review of neurobiology
January 1, 2025
Iva Totomanova, Eline C H M Haijen, Petra P M Hurks et al.
Small doses of LSD and psilocybin produce subtle acute effects on neural connectivity, brain electrophysiology, blood pressure, sleep duration, pain perception, temporal processing, and mood, and reduce symptoms of depression and obsessive-compulsive behavior in patient samples. Extra-pharmacological factors such as baseline subjective state, expectations, and individual differences in drug metabolism influence treatment outcomes. Controlled microdosing studies suggest potential therapeutic applications, but large-scale clinical trials are still needed.