Intrinsic functional connectivity of the brain swallowing network during subliminal esophageal acid stimulation. Neurogastroenterol Motil 2013 Dec;25(12):992-e779
Date
11/21/2013Pubmed ID
24251873Pubmed Central ID
PMC3864683DOI
10.1111/nmo.12238Scopus ID
2-s2.0-84888039500 (requires institutional sign-in at Scopus site) 12 CitationsAbstract
BACKGROUND: Intrinsic synchronous fluctuations of the functional magnetic resonance imaging signal are indicative of the underlying 'functional connectivity' (FC) and serve as a technique to study dynamics of the neuronal networks of the human brain. Earlier studies have characterized the functional connectivity of a distributed network of brain regions involved in swallowing, called brain swallowing network (BSN). The potential modulatory effect of esophageal afferent signals on the BSN, however, has not been systematically studied.
METHODS: Fourteen healthy volunteers underwent steady state functional magnetic resonance imaging across three conditions: (i) transnasal catheter placed in the esophagus without infusion; (ii) buffer solution infused at 1 mL/min; and (iii) acidic solution infused at 1 mL/min. Data were preprocessed according to the standard FC analysis pipeline. We determined the correlation coefficient values of pairs of brain regions involved in swallowing and calculated average group FC matrices across conditions. Effects of subliminal esophageal acidification and nasopharyngeal intubation were determined.
KEY RESULTS: Subliminal esophageal acid stimulation augmented the overall FC of the right anterior insula and specifically the FC to the left inferior parietal lobule. Conscious stimulation by nasopharyngeal intubation reduced the overall FC of the right posterior insula, particularly the FC to the right prefrontal operculum.
CONCLUSIONS & INFERENCES: The FC of BSN is amenable to modulation by sensory input. The modulatory effect of sensory pharyngoesophageal stimulation on BSN is mainly mediated through changes in the FC of the insula. The alteration induced by subliminal visceral esophageal acid stimulation is in different insular connections compared with that of conscious somatic pharyngeal stimulation.
Author List
Babaei A, Siwiec RM, Kern M, Douglas Ward B, Li SJ, Shaker RAuthor
Reza Shaker MD Assoc Provost, Sr Assoc Dean, Ctr Dir, Chief, Prof in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdultBrain
Brain Mapping
Deglutition
Esophagus
Female
Healthy Volunteers
Humans
Hydrochloric Acid
Magnetic Resonance Imaging
Male
Nerve Net
Subliminal Stimulation
Young Adult