title: Reduced hippocampal functional connectivity in Alzheimer disease.
abstract: OBJECTIVE
  To determine if functional connectivity of the hippocampus is reduced in patients with Alzheimer disease.
  
  
  METHODS
  Functional connectivity magnetic resonance imaging was used to investigate coherence in the magnetic resonance signal between the hippocampus and all other regions of the brain.
  
  
  METHODS
  Eight patients with probable Alzheimer disease and 8 healthy volunteers.
  
  
  RESULTS
  Control subjects showed hippocampal functional connectivity with diffuse cortical, subcortical, and cerebellar sites, while patients demonstrated markedly reduced functional connectivity, including an absence of connectivity with the frontal lobes.
  
  
  CONCLUSIONS
  These findings suggest a functional disconnection between the hippocampus and other brain regions in patients with Alzheimer disease.
authors.affiliation: Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9127, USA. Greg.Allen@UTSouthwestern.edu
authors.forename: Greg
authors.initials: G
authors.lastname: Allen
authors.forename: Holly
authors.initials: H
authors.lastname: Barnard
authors.forename: Roderick
authors.initials: R
authors.lastname: McColl
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Hester
authors.forename: Julie A
authors.initials: JA
authors.lastname: Fields
authors.forename: Myron F
authors.initials: MF
authors.lastname: Weiner
authors.forename: Wendy K
authors.initials: WK
authors.lastname: Ringe
authors.forename: Anne M
authors.initials: AM
authors.lastname: Lipton
authors.forename: Matthew
authors.initials: M
authors.lastname: Brooker
authors.forename: Elizabeth
authors.initials: E
authors.lastname: McDonald
authors.forename: Craig D
authors.initials: CD
authors.lastname: Rubin
authors.forename: C Munro
authors.initials: CM
authors.lastname: Cullum
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology; D003627:Data Interpretation, Statistical; D005260:Female; D005625:Frontal Lobe / Q000473:pathology; D007839:Functional Laterality / Q000502:physiology; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D009434:Neural Pathways / Q000473:pathology; D009483:Neuropsychological Tests