title: A functional magnetic resonance imaging study of human brain in pain-related areas induced by electrical stimulation with different intensities.
abstract: BACKGROUND
  Pain-related studies have mainly been performed through traditional methods, which lack the rigorous analysis of anatomical locations. Functional magnetic resonance imaging (fMRI) is a noninvasive method detecting neural activity, and has the ability to precisely locate related activations in vivo. Moreover, few studies have used painful stimulation of changed intensity to investigate relevant functioning nuclei in the human brain.
  
  
  OBJECTIVE
  This study mainly focused on the pain-related activations induced by electrical stimulation with different intensities using fMRI. Furthermore, the electrophysiological characteristics of different pain-susceptible-neurons were analyzed to construct the pain modulatory network, which was corresponding to painful stimulus of changed intensity.
  
  
  METHODS
  Twelve volunteers underwent functional scanning receiving different electrical stimulation. The data were collected and analyzed to generate the corresponding functional activation maps and response time curves related to pain.
  
  
  RESULTS
  The common activations were mainly located in several specific regions, including the secondary somatosensory cortex (SII), insula, anterior cingulate cortex (ACC), thalamus, and other cerebral regions. Moreover, innocuous electrical stimulation primarily activated the lateral portions of SII and thalamus, as well as the posterior insula, anterior ACC, whereas noxious electrical stimulation primarily activated the medial portions of SII and thalamus, as well as the anterior insula, the posterior ACC, with larger extensions and greater intensities.
  
  
  CONCLUSIONS
  Several specified cerebral regions displayed different response patterns during electrical stimulation by means of fMRI, which implied that the corresponding pain-susceptible-neurons might process specific aspects of pain. Elucidation of functions on pain-related regions will help to understand the delicate pain modulation of human brain.
authors.affiliation: Department of Medical Imaging, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Yuan
authors.forename: Zhang
authors.initials: Z
authors.lastname: Ming
authors.forename: Netra
authors.initials: N
authors.lastname: Rana
authors.forename: Liu
authors.initials: L
authors.lastname: Hai
authors.forename: Jin
authors.initials: J
authors.lastname: Chen-wang
authors.forename: Ma
authors.initials: M
authors.lastname: Shao-hui
mesh_terms: D000328:Adult; D055592:Biophysical Phenomena; D001921:Brain / Q000098:blood supply* / Q000503:physiopathology; D001931:Brain Mapping; D004558:Electric Stimulation / Q000009:adverse effects*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010100:Oxygen / Q000097:blood; D010146:Pain / Q000209:etiology* / Q000473:pathology*; D010147:Pain Measurement / Q000379:methods; D055815:Young Adult
chemical_list: D010100:Oxygen