title: Fibromyalgia patients have reduced hippocampal volume compared with healthy controls.
abstract: OBJECTIVE
  Fibromyalgia patients frequently report cognitive abnormalities. As the hippocampus plays an important role in learning and memory, we determined whether individuals with fibromyalgia had smaller hippocampal volume compared with healthy control participants.
  
  
  METHODS
  T1-weighted structural magnetic resonance imaging (MRI) scans were acquired from 40 female participants with fibromyalgia and 22 female healthy controls. The volume of the hippocampus was estimated using the software FreeSurfer. An analysis of covariance model controlling for potentially confounding factors of age, whole brain size, MRI signal quality, and Beck Depression Inventory scores were used to determine significant group differences.
  
  
  RESULTS
  Fibromyalgia participants had significantly smaller hippocampi in both left (F[1,56]=4.55, P=0.037, η (2) p=0.08) and right hemispheres (F[1,56]=5.89, P=0.019, η (2) p=0.10). No significant effect of depression was observed in either left or right hemisphere hippocampal volume (P=0.813 and P=0.811, respectively).
  
  
  CONCLUSIONS
  Potential mechanisms for reduced hippocampal volume in fibromyalgia include abnormal glutamate excitatory neurotransmission and glucocorticoid dysfunction; these factors can lead to neuronal atrophy, through excitotoxicity, and disrupt neurogenesis in the hippocampus. Hippocampal atrophy may play a role in memory and cognitive complaints among fibromyalgia patients.
authors: Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA.
authors: Christina S
authors: CS
authors: McCrae
authors: Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA.
authors: Andrew M
authors: AM
authors: O'Shea
authors: Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA.
authors: Jeff
authors: J
authors: Boissoneault
authors: Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA.
authors: Karlyn E
authors: KE
authors: Vatthauer
authors: Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA ; Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA.
authors: Michael E
authors: ME
authors: Robinson
authors: Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA ; College of Medicine, University of Florida, Gainesville, FL, USA.
authors: Roland
authors: R
authors: Staud
authors: McKnight Brain Institute, University of Florida, Gainesville, FL, USA ; Department of Psychiatry, University of Florida, Gainesville, FL, USA ; Malcom Randall Veterans Administration Medical Center, Gainesville, FL, USA ; Rehabilitation Research and Development Brain Research Center of Excellence, Veterans Administration Medical Center, Gainesville, FL, USA.
authors: William M
authors: WM
authors: Perlstein
authors: Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA.
authors: Jason G
authors: JG
authors: Craggs
keywords: MRI; brain atrophy; hippocampus; pain