title: Continuous Descending Modulation of the Spinal Cord Revealed by Functional MRI.
abstract: Spontaneous variations in spinal cord activity may arise from regulation of any of a number of functions including sensory, motor, and autonomic control. Here, we use functional MRI (fMRI) of healthy participants to identify properties of blood oxygenation-level dependent (BOLD) variations in the spinal cord in response to knowledge that either a noxious stimulus is impending, or that no stimulus is to be expected. Expectation of a noxious stimulus, or no stimulus, is shown to have a significant effect on wide-spread BOLD signal variations in the spinal cord over the entire time period of the fMRI acquisition. Coordination of BOLD responses between/within spinal cord and brainstem regions are also influenced by this knowledge. We provide evidence that such signal variations are the result of continuous descending modulation of spinal cord function. BOLD signal variations in response to noxious stimulation of the hand are also shown, as in previous studies. The observation of both continuous and reactive BOLD responses to emotional/cognitive factors and noxious peripheral stimulation may have important implications, not only for our understanding of endogenous pain modulation, but also in showing that spinal cord activity is under continuous regulatory control.
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.|Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.|Department of Physics, Queen's University, Kingston, Ontario, Canada.
authors.forename: Patrick W
authors.identifier: http://orcid.org/0000-0002-9814-260X
authors.initials: PW
authors.lastname: Stroman
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: Rachael L
authors.initials: RL
authors.lastname: Bosma
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: Andreea I
authors.initials: AI
authors.lastname: Cotoi
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: Roxanne H
authors.initials: RH
authors.lastname: Leung
authors.affiliation: Dept of Radiology, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Kornelsen
authors.affiliation: Thunder Bay Regional Research Institute, Thunder Bay, Ontario, Canada.
authors.forename: Jane M
authors.initials: JM
authors.lastname: Lawrence-Dewar
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.|Department of Psychology, Queen's University, Kingston, Ontario, Canada.
authors.forename: Caroline F
authors.initials: CF
authors.lastname: Pukall
authors.affiliation: Department of Medicine, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Roland
authors.initials: R
authors.lastname: Staud
mesh_terms: D000328:Adult; D001933:Brain Stem / Q000502:physiology; D055724:Electrophysiological Phenomena; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood / Q000378:metabolism; D010146:Pain / Q000503:physiopathology; D058748:Pain Perception; D013116:Spinal Cord / Q000098:blood supply / Q000502:physiology*; D055815:Young Adult
chemical_list: D010100:Oxygen