Overview

• Researchers at the Salk Institute mapped a previously unknown spinothalamic branch in mice where CGRP-expressing thalamic neurons relay pain signals directly to the amygdala.
• Genetic silencing of these CGRP neurons left physical pain detection intact but abolished learned fear and avoidance behaviors in mice.
• Optogenetic activation of the same neurons induced distress and avoidance even without any actual pain stimulus.
• Transcriptomic analysis revealed that the identified CGRP neurons express genes associated with migraine and other chronic pain disorders.
• The team is exploring whether approved CGRP-blocking drugs can alleviate the emotional dimension of pain and examining the pathway’s role in PTSD and hypervigilance.