GlossaryTrigeminal pathway

Trigeminal pathway

The trigeminal nerve system (cranial nerve V) responsible for transmitting pain signals from the face, scalp, and meninges to the brain. Becomes sensitised and hyperactivated during cluster headache and migraine attacks. Psilocybin may modulate trigeminal pain pathways via 5-HT2B and 5-HT2C receptor activity — a mechanism distinct from its 5-HT2A-mediated antidepressant effects. This distinction may explain why psilocybin's headache benefits do not correlate with psychedelic intensity.

Full Explanation

The trigeminal pathway is the trigeminal nerve system (cranial nerve V) responsible for transmitting pain signals from the face, scalp, and meninges to the brain. It becomes sensitised and hyperactivated during cluster headache and migraine attacks. Psilocybin may modulate trigeminal pain pathways via 5-HT2B and 5-HT2C receptor activity — a mechanism distinct from its 5-HT2A-mediated antidepressant effects. This distinction may explain why psilocybin's headache benefits do not correlate with psychedelic intensity.

See: Cluster Headaches (/conditions/cluster-headaches).

Why It Matters

The trigeminal pathway explains why psilocybin can help cluster headache through a different mechanism than depression — and why sub-psychedelic doses can still be effective.