Psilocybin-Induced Decrease in Amygdala Reactivity Correlates with Enhanced Positive Mood in Healthy Volunteers
Rainer Kraehenmann, Katrin H. Preller, Milan Scheidegger, Thomas Pokorny, Oliver G. Bosch, Erich Seifritz, Franz X. Vollenweider
Biological Psychiatry April 26, 2014 DOI: 10.1016/j.biopsych.2014.04.010 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Double-blind Peer reviewed |
|---|---|
| Sample size | 25 |
| Population | Healthy volunteers |
| Intervention | Psilocybin |
| Dose | 0.16 mg/kg |
| Duration | Two separate sessions at least 14 days apart |
| Topics | Psilocybin Serotonin |
| Keywords | Amygdala Mood Hallucinogen Placebo Reactivity psychology Clinical psychology Receptor |
| Citations | 325 |
| Key findings | Acute psilocybin administration reduced amygdala reactivity to negative stimuli and increased positive mood, with the reduction in right amygdala reactivity linked to the mood improvement. |
Abstract
BackgroundThe amygdala is a key structure in serotonergic emotion-processing circuits. In healthy volunteers, acute administration of the serotonin 1A/2A/2C receptor agonist psilocybin reduces neural responses to negative stimuli and induces mood changes toward positive states. However, it is little-known whether psilocybin reduces amygdala reactivity to negative stimuli and whether any change in amygdala reactivity is related to mood change.MethodsThis study assessed the effects of acute administration of the hallucinogen psilocybin (.16 mg/kg) versus placebo on amygdala reactivity to negative stimuli in 25 healthy volunteers using blood oxygen level-dependent functional magnetic resonance imaging. Mood changes were assessed using the Positive and Negative Affect Schedule and the state portion of the State-Trait Anxiety Inventory. A double-blind, randomized, cross-over design was used with volunteers counterbalanced to receive psilocybin and placebo in two separate sessions at least 14 days apart.ResultsAmygdala reactivity to negative and neutral stimuli was lower after psilocybin administration than after placebo administration. The psilocybin-induced attenuation of right amygdala reactivity in response to negative stimuli was related to the psilocybin-induced increase in positive mood state.ConclusionsThese results demonstrate that acute treatment with psilocybin decreased amygdala reactivity during emotion processing and that this was associated with an increase of positive mood in healthy volunteers. These findings may be relevant to the normalization of amygdala hyperactivity and negative mood states in patients with major depression.
Comparable studies
Other randomized controlled trials on psilocybin, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial Cancer patients with life-threatening diagnoses and symptoms of depression and/or anxiety | 2016 | Randomized controlled trial | n = 51 |
| Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: a randomized controlled trial Patients with cancer-related anxiety and depression | 2016 | Double-blind, placebo-controlled, crossover trial | n = 29 |
| Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance Hallucinogen-naïve adults reporting regular participation in religious or spiritual... | 2006 | Double-blind study | n = 36 |
| Trial of Psilocybin versus Escitalopram for Depression Selected group of patients with depression | 2021 | Randomized controlled trial | |
| Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder Adults aged 21 to 75 years with major depressive disorder, not currently using... | 2020 | Randomized controlled trial | n = 24 |
Citations in the library
Cited by 263
- REBUS and the Anarchic Brain: Toward a Unified Model of the Brain Action of Psychedelics Pharmacological Reviews June 20, 2019
- Psilocybin-Occasioned Mystical Experiences in the Treatment of Tobacco Addiction Current Drug Abuse Reviews January 9, 2015
- Classic psychedelic use is associated with reduced psychological distress and suicidality in the United States adult population. Journal of Psychopharmacology March 1, 2015
- Emotions and brain function are altered up to one month after a single high dose of psilocybin. Scientific Reports February 10, 2020
- The Challenging Experience Questionnaire: Characterization of challenging experiences with psilocybin mushrooms Journal of Psychopharmacology November 18, 2016
and 258 more in the library
Cites 18
- Pilot Study of Psilocybin Treatment for Anxiety in Patients With Advanced-Stage Cancer Archives of General Psychiatry September 7, 2010
- Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin Proceedings of the National Academy of Sciences January 23, 2012
- Psilocybin induces schizophrenia-like psychosis in humans via a serotonin-2 agonist action Neuroreport December 1, 1998
- Acute psychological and physiological effects of psilocybin in healthy humans: a double-blind, placebo-controlled dose?effect study Psychopharmacology March 1, 2004
- Serotonin, via 5-HT2A receptors, increases EPSCs in layer V pyramidal cells of prefrontal cortex by an asynchronous mode of glutamate release Brain Research April 1, 1999
and 13 more in the library