title: Effects of hypoglycemia on human brain activation measured with fMRI.
abstract: Functional magnetic resonance imaging (fMRI) was used to measure the effects of acute hypoglycemia caused by passive sensory stimulation on brain activation. Visual stimulation was used to generate blood-oxygen-level-dependent (BOLD) contrast, which was monitored during hyperinsulinemic hypoglycemic and euglycemic clamp studies. Hypoglycemia (50 +/- 1 mg glucose/dl) decreased the fMRI signal relative to euglycemia in 10 healthy human subjects: the fractional signal change was reduced by 28 +/- 12% (P < .05). These changes were reversed when euglycemia was restored. These data provide a basis of comparison for studies that quantify hypoglycemia-related changes in fMRI activity during cognitive tasks based on visual stimuli and demonstrate that variations in blood glucose levels may modulate BOLD signals in the healthy brain.
authors.affiliation: Department of Biomedical Engineering, School of Engineering, Vanderbilt University, Nashville, TN 37232-2675, USA. adam.anderson@vanderbilt.edu
authors.forename: Adam W
authors.initials: AW
authors.lastname: Anderson
authors.forename: Rubina A
authors.initials: RA
authors.lastname: Heptulla
authors.forename: Naomi
authors.initials: N
authors.lastname: Driesen
authors.forename: Daniel
authors.initials: D
authors.lastname: Flanagan
authors.forename: Philip A
authors.initials: PA
authors.lastname: Goldberg
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Jones
authors.forename: Fran
authors.initials: F
authors.lastname: Rife
authors.forename: Hedy
authors.initials: H
authors.lastname: Sarofin
authors.forename: William
authors.initials: W
authors.lastname: Tamborlane
authors.forename: Robert
authors.initials: R
authors.lastname: Sherwin
authors.forename: John C
authors.initials: JC
authors.lastname: Gore
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001931:Brain Mapping / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D004837:Epinephrine / Q000097:blood; D005934:Glucagon / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007003:Hypoglycemia / Q000503:physiopathology*; D007328:Insulin / Q000097:blood; D008279:Magnetic Resonance Imaging; D009638:Norepinephrine / Q000097:blood; D010775:Photic Stimulation; D011863:Radioimmunoassay; D014793:Visual Cortex / Q000503:physiopathology*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D005934:Glucagon; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine