Resting-state brain and spinal cord networks in humans are functionally integrated.

Shahabeddin Vahdat,Julien Doyon,Christian Büchel,Ovidiu Lungu,Ali Khatibi,Veronique Marchand-Pauvert,Jürgen Finsterbusch,Julien Cohen-Adad,Ed T Bullmore

doi:10.1371/journal.pbio.3000789

Abstract

In the absence of any task, both the brain and spinal cord exhibit spontaneous intrinsic activity organised in a set of functionally relevant neural networks. However, whether such resting-state networks (RSNs) are interconnected across the brain and spinal cord is unclear. Here, we used a unique scanning protocol to acquire functional images of both brain and cervical spinal cord (CSC) simultaneously and examined their spatiotemporal correspondence in humans. We show that the brain and spinal cord activities are strongly correlated during rest periods, and specific spinal cord regions are functionally linked to consistently reported brain sensorimotor RSNs. The functional organisation of these networks follows well-established anatomical principles, including the contralateral correspondence between the spinal hemicords and brain hemispheres as well as sensory versus motor segregation of neural pathways along the brain–spinal cord axis. Thus, our findings reveal a unified functional organisation of sensorimotor networks in the entire central nervous system (CNS) at rest.

Highlights

Spontaneous modulations of the blood-oxygen–level dependent (BOLD) signals from functional magnetic resonance imaging in the absence of any overt task or stimulation have been well characterised in the human brain [1,2]
We provide the first neuroimaging evidence for the existence of resting-state functional networks spanning both the brain and spinal cord structures
Our findings reveal a close relationship between spontaneous activities of different brain areas with musculoskeletal afferent and efferent intrinsic activities, which may reflect a functional property of the entire central nervous system (CNS) at rest

Summary

Introduction

Spontaneous modulations of the blood-oxygen–level dependent (BOLD) signals from functional magnetic resonance imaging (fMRI) in the absence of any overt task or stimulation have been well characterised in the human brain [1,2]. These slow fluctuations partition the resting brain into temporally synchronised networks of spatially distinct areas, the so-called restingstate networks (RSNs), which mimics the clusters of brain regions that are co-activated during the performance of different sensorimotor and cognitive tasks [2]. Integrated brain and spinal cord networks analysis, decision to publish, or preparation of the manuscript

Methods

Results

Conclusion