Faculty Collaboration Database

Intrinsic functional connectivity of the brain swallowing network during subliminal esophageal acid stimulation. Neurogastroenterol Motil 2013 Dec;25(12):992-e779

Date

11/21/2013

Pubmed ID

24251873

Pubmed Central ID

PMC3864683

DOI

10.1111/nmo.12238

Scopus ID

2-s2.0-84888039500 (requires institutional sign-in at Scopus site)   12 Citations

Abstract

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 R

Author

Reza Shaker MD Assoc Provost, Sr Assoc Dean, Ctr Dir, Chief, Prof in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Brain
Brain Mapping
Deglutition
Esophagus
Female
Healthy Volunteers
Humans
Hydrochloric Acid
Magnetic Resonance Imaging
Male
Nerve Net
Subliminal Stimulation
Young Adult