You may have heard about the mental health benefits of psilocybin, but have you ever wondered how this substance actually affects the brain? The neuroscience and pharmacokinetics behind psilocybin and other psychedelics can get very complicated, but we’ve made it easy to understand.

In this blog post, we’re going to break down what happens to your brain on psilocybin. We’ll explore how psilocybin works in comparison to current pharmaceutical antidepressants, including how psilocybin affects serotonin receptors, the claustrum, neuroplasticity, and what it all means.

We’ll conclude by taking a look at brand new research that has mapped the brain using fMRI brain scans from nearly 60 people who had participated in two psilocybin trials. Next is the answer to your question, and this is what happens to your brain on psilocybin.

Serotonin Receptors and Psilocybin

Psilocybin binds to and activates 5-HT2A serotonin receptors, which can cause hallucinogenic.  experiences. 

Older research on psilocybin and serotonin receptors found evidence to “support the hypothesis that psilocybin and other classical hallucinogens exert their psychedelic actions in humans via activating 5-HT2A serotonin receptors.”

These are the same receptors that are targeted by many current antidepressant medications, which is why research is finding psilocybin to be so helpful in treating depression.

The Claustrum and Psilocybin

Newer research has examined the effects of psilocybin on the claustrum. The claustrum is a small area of the brain that is thought to be involved in consciousness.

Psilocybin affects the claustrum by causing it to become less active. Research on the claustrum and psilocybin has found that,

“Psilocybin significantly decreased both the amplitude of low frequency fluctuations as well as the variance of blood-oxygenation level-dependent signal in the left and right claustrum. Psilocybin also significantly decreased functional connectivity of the right claustrum with auditory and default mode networks, increased right claustrum connectivity with the frontoparietal task control network, and decreased left claustrum connectivity with the frontoparietal task control network.”

In other words, scientists found that taking psilocybin turns down the brain’s natural areas responsible for attention and tasks. Researchers suggest these effects on the claustrum are what cause reported feelings of reduced ego, increased empathy, and an overall feeling of connection to everything.

Frederick Barrett, Ph.D., assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, told reporters,

”Our findings move us one step closer to understanding mechanisms underlying how psilocybin works in the brain. This will hopefully enable us to better understand why it’s an effective therapy for certain psychiatric disorders, which might help us tailor therapies to help people more.”

Neuroplasticity and Psilocybin

Psilocybin also affects neuroplasticity, which is responsible for the organization and reorganization of synaptic connections, often triggered by responses to new experiences. Improve neuroplasticity is linked to improved mental health, including reduced anxiety and depression.

Scientists have known this for some time, but new research has discovered that

“The window of neuroplasticity appears to open within a few hours and may last a few days (after consuming psilocybin) although neuroplastic changes occurring during this time may survive for at least a month. Because neuroplastic changes occur in an experience-dependent manner, experiences people have during this time may have a greater psychological impact than they otherwise would.”

These greater psychological impacts are what researchers believe contribute to the short and long-term effects of psilocybin in treating conditions like depression and addiction. 

New Research on Psilocybin and the Brain

A brand new study on how psilocybin affects the brain has used fMRI brain scans to map the brains of nearly 60 people who had participated in two psilocybin trials. The results of this study showed that,

“For the first time we find that psilocybin works differently from conventional antidepressants – making the brain more flexible and fluid, and less entrenched in the negative thinking patterns associated with depression. This supports our initial predictions and confirms psilocybin could be a real alternative approach to depression treatments.”

David Nutt, DM, head of the Imperial Centre for Psychedelic Research

All of this research gives us a better idea of what happens to your brain on psilocybin. However, this is just a snapshot of some of what we know about how psilocybin affects the brain. There is still much to be learned about this substance, but so far, the mechanisms of action in the brain triggered by psilocybin are proving to be helpful for many mental health conditions.