Interoception represents a fundamental pathway through which the nervous system monitors our internal states. The cerebrospinal fluid—a complex solution that bathes and protects our brain and spinal cord—serves as more than just a protective medium. Just as medical doctors perform spinal taps to diagnose infections or neurological diseases, we have discovered, using transparent larval zebrafish as a model system, that the body possesses its own system for detecting changes in cerebrospinal fluid to regulate posture, movement capabilities, innate immunity, and morphogenesis. Claire Wyart will discuss how small neurons in the spinal cord act as sophisticated mechanosensors to detect spinal compression and modulate appropriate responses. This opens new avenues for understanding how our bodies integrate internal conditions with external physical expression.
