The Fascinating Effects of Psilocybin on the Brain
- Pysilly Spores
- 3 days ago
- 3 min read
Understanding Psilocybin and Its Impact
When people hear “psilocybin,” they often think of psychedelic drugs. Images of the unbridled 60s, after-hours parties, and the Grateful Dead come to mind. This compound is the common ingredient in “magic mushrooms.” For decades, advocates for psychedelics have promoted the therapeutic benefits of psilocybin. Recently, mainstream medical research has taken a closer look.
We already knew that psilocybin has long-lasting and wide-ranging effects on the brain. For example, it has shown promise in treating depression and potentially substance use disorders, with benefits lasting weeks to months. However, a new study01305-4?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867425013054%3Fshowall%3Dtrue) reveals that it also has a long-lasting effect on the physical structure of the brain’s connections.
How Psilocybin Changes Brain Structure
Just one dose of psilocybin alters the structure of dendritic spines. These tiny protrusions are where neurons receive signals from other neurons. This change occurs in the medial frontal cortex, an area crucial for decision-making and regulating social behavior in mice. Scientists were initially unsure which regions of the brain were sending signals to these newly formed connections. Understanding this could help researchers learn how psilocybin creates lasting changes in the brain.
“The rewiring in the mouse brain from psilocybin is not haphazard; there’s a definite pattern to it,” said Alex Kwan, Ph.D., a professor of biomedical engineering at Cornell University and one of the senior authors of the study.
Research Techniques and Findings
Researchers employed several tools from the Allen Institute, including the Allen Mouse Connectivity Database. They also used specially engineered harmless viruses that can’t replicate and the OpenEphys GUI open-source tool. The engineered virus helped map connections throughout the entire mouse brain. This was extremely helpful, as the virus inserted special DNA into brain cells, causing them to glow. This allowed researchers to trace and track connected cells.
The focus was on two major types of neurons in the front part of the brain: pyramidal tract (PT) neurons and intratelencephalic (IT) neurons. Both are excitatory neurons that send electrical signals to different areas of the brain. Some mice received psilocybin, while others received saline. The results showed significant differences in drug-induced wiring changes between the PT and IT neurons.
The Dual Effects on Neurons
Psilocybin strengthened the connections into PT neurons from regions of the brain that control senses. This includes the visual cortex, which processes what the animal sees, and the retrosplenial cortex, which aids in navigation, memory, and spatial orientation. However, this strengthening came at a cost. Connections from other regions weakened, particularly from the lateral network and the ventromedial prefrontal cortex. These areas regulate the animal’s bodily and emotional responses.
Conversely, IT neurons showed the opposite response. Psilocybin weakened the connections into these neurons that were strengthened in PT neurons. This suggests that psilocybin isn’t merely amplifying or dampening brain activity. Instead, it orchestrates a coordinated reorganization of information flow through the brain’s networks. Researchers believe that the pattern of rewiring depends on the firing activity of neurons. For instance, psilocybin increased the firing rate of neurons in the retrosplenial cortex by 39%.
“Illuminating the specific pathways that psilocybin acts on was an important breakthrough in this study,” Kwan stated. “We also used chemogenetics to determine the drug’s effect on the plasticity of the brain. It appears that the plasticity depends not only on the influence of psilocybin but also on the ongoing brain activity.”
Implications for Psychedelic Therapy
Researchers hope the findings from this study can enhance psychedelic therapy. If neural activity during drug exposure determines which circuits get rewired, combining psilocybin with targeted brain stimulation techniques could guide brain cell rewiring toward specific therapeutic circuits. While scientists acknowledge that humans suffering from mental illness or depression differ from lab mice in controlled environments, these insights could inform how psilocybin is administered.
By varying the dosage, controlling external stimuli, or adjusting other variables, researchers can better account for individual reactions to psilocybin. Understanding which circuits are affected can lead to more targeted therapeutics.
Conclusion: The Future of Psilocybin Research
The research into psilocybin and its effects on the brain is still evolving. As we uncover more about how psilocybin rewires neural connections, we may unlock new pathways for treating mental health conditions. This could lead to more effective therapies and a deeper understanding of the brain's complexities.
For those interested in exploring the world of mushroom cultivation, understanding the science behind psilocybin can be a fascinating journey. Whether you are a beginner or have some experience, the potential benefits of growing your own mushrooms can be both rewarding and enlightening.
