When emotions are processed in a negatively biased manner in the brain, an individual is at risk to develop depression. Psilocybin, the bioactive component of the Mexican magic mushroom, seems to intervene positively in the emotion-processing mechanism. Even a small amount of the natural substance attenuates the processing of negative emotions and brightens mood as shown by UZH researchers using imaging methods.
Emotions like fear, anger, sadness, and joy enable people to adjust to their environment and react flexibly to stress and strain and are vital for cognitive processes, physiological reactions, and social behaviour. The processing of emotions is closely linked to structures in the brain, i.e. to what is known as the limbic system.
Within this system the amygdala plays a central role – above all it processes negative emotions like anxiety and fear. If the activity of the amygdala becomes unbalanced, depression and anxiety disorders may develop.
Researchers at the Psychiatric University Hospital of Zurich have now shown that psilocybin, the bioactive component in the Mexican magic mushroom, influences the amygdala, thereby weakening the processing of negative stimuli. These findings could “point the way to novel approaches to treatment” comments the lead author Rainer Krähenmann on the results which have now been published in the renowned medical journal “Biological Psychiatry”.
Psilocybin inhibits the processing of negative emotions in the amygdala
The processing of emotions can be impaired by various causes and elicit mental disorders. Elevated activity of the amygdala in response to stimuli leads to the neurons strengthening negative signals and weakening the processing of positive ones. This mechanism plays an important role in the development of depression and anxiety disorders. Psilocybin intervenes specifically in this mechanism as shown by Dr. Rainer Krähenmann's research team of the Neuropsychopharmacology and Brain Imaging Unit led by Prof. Dr. Franz Vollenweider.
Psilocybin positively influences mood in healthy individuals. In the brain, this substance stimulates specific docking sites for the messenger serotonin. The scientists therefore assumed that psilocybin exerts its mood-brightening effect via a change in the serotonin system in the limbic brain regions. This could, in fact, be demonstrated using functional magnetic resonance imaging (fMRI). “Even a moderate dose of psilocybin weakens the processing of negative stimuli by modifying amygdala activity in the limbic system as well as in other associated brain regions”, continues Krähenmann. The study clearly shows that the modulation of amygdalaactivity is directly linked to the experience of heightened mood.
Next study with depressive patients
According to Krähenmann, this observation is of major clinical importance. Depressive patients in particular react more to negative stimuli and their thoughts often revolve around negative contents. Hence, the neuropharmacologists now wish to elucidate in further studies whether psilocybin normalises the exaggerated processing of negative stimuli as seen in neuroimaging studies of depressedpatients - and may consequently lead to improved mood in these patients. .
Rainer Krähenmann considers research into novel approaches to treatment very important, because current available drugs for the treatment of depression and anxiety disorders are not effective in all patients and are often associated with unwanted side effects.
Rainer Kraehenmann, Katrin H. Preller, Milan Scheidegger, Thomas Pokorny, Oliver G. Bosch, Erich Seifritz, Franz X. Vollenweider,(in press). Psilocybin-Induced Decrease in Amygdala Reactivity Correlates with Enhanced Positive Mood in Healthy Volunteers. Biological Psychiatry. http://dx.doi.org/10.1016/j.biopsych.2014.04.010
Prof. Dr. Franz Vollenweider
Psychiatric University Hospital of Zurich
University of Zurich
Tel.: +41 44 384 24 04
Dr. Katrin Preller
Psychiatric University Hospital of Zurich (PUKZH)
University of Zurich
Tel.: +41 44 384 26 25
University of Zurich
Tel. +41 44 634 44 64
Nathalie Huber | Universität Zürich
PRB projects world population rising 33 percent by 2050 to nearly 10 billion
25.08.2016 | Population Reference Bureau
Just add water? New MRI technique shows what drinking water does to your appetite, stomach and brain
12.07.2016 | Society for the Study of Ingestive Behavior
Scientists and engineers striving to create the next machine-age marvel--whether it be a more aerodynamic rocket, a faster race car, or a higher-efficiency jet...
Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.
In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...
Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.
Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...
Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...
A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.
25.08.2016 | Event News
24.08.2016 | Event News
12.08.2016 | Event News
29.08.2016 | Materials Sciences
29.08.2016 | Life Sciences
29.08.2016 | Medical Engineering