Potential of Psilocybin in Mental Health Therapy
Over the past 50 years, tens of millions of people have used entheogens, yet there just is not much scientific evidence on either positive or negative long-term effects of these substances. The classical psychedelics (LSD, psilocybin, etc.) are not known to cause brain damage and are regarded as non-addictive. Research has also concluded there are no significant associations between lifetime and recent use of entheogens and no increased rate of mental health outcomes.
Rather, in several cases entheogen use was associated with a lower rate of mental health problems. A recent study at the Psychiatric University Hospital of Zurich has shown that psilocybin, the bioactive component in the Mexican “magic mushroom,” influences the amygdala, thereby weakening the processing of negative stimuli. The amygdala is a key structure in serotonergic emotion-processing circuits. A double blind, randomized, crossover design was used with 25 volunteers counterbalanced to receive psilocybin and placebo in two separate sessions at least 14 days apart.
These 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 negative mood states in patients with major depression.
Lead author Dr. Rainer Krähenmann commented:
“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.”
The study clearly shows that the modulation of amygdala activity is directly linked to the experience of heightened mood. This observation is of major clinical importance, which could lead to novel approaches to treatments of mental health disorders. Depressive patients in particular react more to negative stimuli and their thoughts often revolve around negative content. Minimal treatment may have potential to improved mood in depressed patients and prevent risk associated with long-term antidepressant dependency.
In another new study, researchers found that our brain displays a similar pattern of activity during dreams as it does during a mind-expanding entheogen experience. The study found that under psilocybin, activity in the more primitive brain network linked to emotional thinking became more pronounced, with several different areas in this network, such as the hippocampus and anterior cingulate cortex, active at the same time. This pattern of activity is similar to the pattern observed in people who are dreaming. Conversely, volunteers who had taken psilocybin had more disjointed and uncoordinated activity in the brain network that is linked to high-level thinking, including self-consciousness.
Dr. Robin Carhart-Harris from the Department of Medicine, Imperial College London said:
“I was fascinated to see similarities between the pattern of brain activity in a psychedelic state and the pattern of brain activity during dream sleep, especially as both involve the primitive areas of the brain linked to emotions and memory. People often describe taking psilocybin as producing a dream-like state and our findings have, for the first time, provided a physical representation for the experience in the brain.”
The study examined variation in the amplitude of fluctuations in what is called the blood-oxygen level dependent (BOLD) signal, which tracks activity levels in the brain. It is the first time these methods were used to look at brain imaging data and it has given some fascinating insight into how entheogenic drugs expand the mind. Scientists are continuing studies into how psilocybin may help alleviate symptoms of depression by allowing patients to change their rigidly pessimistic patterns of thinking.