Reduced hippocampal functional connectivity in Alzheimer disease.
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.
Allen
Greg
G
Department of Psychiatry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9127, USA. Greg.Allen@UTSouthwestern.edu
Barnard
Holly
H
McColl
Roderick
R
Hester
Andrea L
AL
Fields
Julie A
JA
Weiner
Myron F
MF
Ringe
Wendy K
WK
Lipton
Anne M
AM
Brooker
Matthew
M
McDonald
Elizabeth
E
Rubin
Craig D
CD
Cullum
C Munro
CM
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