Neural computation in the brainstem for visceral sensation-driven haemodynamics

The brainstem serves as an intermediary processor of haemodynamic sensations via nucleus tractus solitaries (NTS) in regulating circulatory system. After sensing visceral inputs, the NTS relays information to efferent pathways to modulate peripheral viscera. However, the neural computation mechanism underlying how the NTS processes viscerosensory input remains unknown. Here, we show the computational principles embedded inside the NTS of rats, producing haemodynamic modulation in concert. Our findings demonstrate that the collective dynamics leveraging from neuronal population within the NTS neural circuit encode input-driven haemodynamics. The NTS exhibits the neural trajectory, the dynamical trace of neural states, which is confined to low-dimensional latent space and may represent haemodynamic perturbations. Surprisingly, by normalizing neural trajectory of rats, we found the across-rat common rules for the viscerosensory-information processing by the NTS. Furthermore, the common rules allowed to identify inter-subject variable haemodynamics by quantifying the computational mechanisms in neuro-haemodynamic axis. Our findings provide pioneering insights into understanding the neural computation involved in regulation of visceral functions by the autonomic nervous system.