Characterization of the Resting-State Functional Dynamics in the Lumbosacral Spinal Cord

In recent years, there has been a growing interest in investigating spontaneous brain activity, with a newfound focus on understanding the resting state activity of the spinal cord due to its importance in sensorimotor interactions. Previous studies have predominantly concentrated on the upper regions of the spinal cord. In particular one study explored functional dynamics in the cervical region utilizing the SpiCiCAP framework to reveal consistent neural activity patterns across individuals, aligning with established neuroanatomical features. The current study seeks to explore, for the first time, the spatial and temporal features of functional dynamics in the lower portion of the spinal cord (specifically, the lumbosacral region) using the same framework. Through the analysis, two distinct sets of components with varying levels of detail are identified, demonstrating generalizability across subjects. Overall, the BOLD signals cluster into regions corresponding to predefined spinal levels. However, as granularity increases, co-activation patterns within each level begin to segregate. Additionally, the study demonstrates that resting state activity within each spinal level exhibits a higher degree of coupling compared to other levels, shedding light on the intricacies of spinal cord functionality during periods of rest.