Neuroplasticity • October 22, 2026
Brain-Derived Neurotrophic Factor (BDNF) and Psilocybin-Induced Dendritic Spinogenesis
Clinical studies show psilocybin rapidly elevates BDNF levels, stimulating TrkB receptor signaling and promoting the growth of new synaptic spines in cortical neurons.
Synaptic Atrophy in Chronic Stress and Mood Disorders
Prolonged exposure to cortisol, environmental stress, and inflammation leads to synaptic loss and dendritic spine retraction in the prefrontal cortex and hippocampus. This structural atrophy is a core pathological hallmark of major depression and PTSD.
The BDNF / TrkB Signaling Cascade
Psilocin binding to 5-HT2A receptors activates intracellular signaling pathways involving mTOR (mammalian target of rapamycin) and triggers the immediate transcription and secretion of Brain-Derived Neurotrophic Factor (BDNF).
BDNF binds to tropomyosin receptor kinase B (TrkB) receptors, initiating an enzymatic cascade that promotes actin polymerization and structural remodeling of dendritic spines within 24 hours of administration.
Therapeutic Implications for Rapid-Onset Antidepressant Effects
Unlike conventional SSRIs which require weeks of daily administration to achieve modest BDNF elevation, a single clinical dose of psilocybin stimulates immediate, sustained synaptogenesis. This explains the rapid and long-lasting remission observed in clinical trials across Canada and globally.