Exploring the brain in pain: Activations, deactivations and their relation

• Published in: Pain (Amsterdam) Vol. 148; no. 2; pp. 257 - 267
• Main Authors: Kong, Jian, Loggia, Marco L., Zyloney, Carolyn, Tu, Peichi, LaViolette, Peter, Gollub, Randy L.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Elsevier B.V 01.02.2010; Lippincott Williams & Wilkins, Inc; Elsevier
• Subjects: Adult; Biological and medical sciences; Brain - blood supply; Brain - physiopathology; Brain Mapping; Cross-modal interaction; Default network; Female; fMRI; Forearm - innervation; Functional connectivity; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Gender difference; Humans; Illness and personality; Illness, stress and coping; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Neural Pathways - blood supply; Oxygen - blood; Pain - pathology; Pain Measurement - methods; Pain Threshold - physiology; Psychology and medicine; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Resting state; Sex Factors; Somesthesis and somesthetic pathways (proprioception, exteroception, nociception); interoception; electrolocation. Sensory receptors; Statistics as Topic; Vertebrates: nervous system and sense organs; Young Adult; Functional connectivity; Default network; fMRI; Resting state; Cross-modal interaction; Gender difference; Noxious stimulus; Sex; Functional analysis; Low intensity; Crossmodal interaction; Nuclear magnetic resonance imaging; Experience; Pain
• ISSN: 0304-3959; 1872-6623; 1872-6623
• DOI: 10.1016/j.pain.2009.11.008

The majority of neuroimaging studies on pain focuses on the study of BOLD activations, and more rarely on deactivations. In this study, in a relatively large cohort of subjects ( N = 61), we assess (a) the extent of brain activation and deactivation during the application of two different heat pain levels (HIGH and LOW) and (b) the relations between these two directions of fMRI signal change. Furthermore, in a subset of our subjects ( N = 12), we assess (c) the functional connectivity of pain-activated or -deactivated regions during resting states. As previously observed, we find that pain stimuli induce intensity dependent (HIGH pain > LOW pain) fMRI signal increases across the pain matrix. Simultaneously, the noxious stimuli induce activity decreases in several brain regions, including some of the ‘core structures’ of the default network (DMN). In contrast to what we observe with the signal increases, the extent of deactivations is greater for LOW than HIGH pain stimuli. The functional dissociation between activated and deactivated networks is further supported by correlational and functional connectivity analyses. Our results illustrate the absence of a linear relationship between pain activations and deactivations, and therefore suggest that these brain signal changes underlie different aspects of the pain experience.