From Anatomy to Function: Critical Questions on the Dynamic Properties of Segregated Visceral Afferent Circuits.

The recent study by Wang et al. (2025) provides a seminal description of the distinct brainstem projections of splanchnic and pelvic spinal afferents from the mouse colorectum, offering a crucial anatomical framework for visceral sensation. In this letter, we critically appraise these findings and delineate essential frontiers for future research. While the anatomical segregation is compelling, we argue that the molecular logic governing synaptic specificity and signal transmission within these circuits remains unexplored. Furthermore, the translational relevance of this map must be tested in models of chronic visceral pain to determine whether maladaptive plasticity underlies functional disorders. Finally, the supraspinal integration of these parallel streams to generate conscious perception represents a critical next step. Moving forward, the field must leverage this foundational map to interrogate the dynamic properties of these circuits, bridging the gap from static anatomy to the lived experience of visceral pain and identifying novel therapeutic targets.