title: Structural and functional imaging of the hippocampus in young people at familial risk of depression.
abstract: BACKGROUND
  Major depression is associated with abnormalities in the function and structure of the hippocampus. However, it is unclear whether these abnormalities might also be present in people 'at risk' of illness.
  
  
  METHODS
  We studied 62 young people (mean age 18.8 years) at familial risk of depression (FH+) but who had never been depressed themselves. Participants underwent magnetic resonance imaging to assess hippocampal structure and neural responses to a task designed to activate hippocampal memory networks. Magnetic resonance spectroscopy was used to measure levels of a combination of glutamine and glutamate (Glx) in the right hippocampus. A total of 59 matched controls with no history of mood disorder in a first-degree relative underwent the same investigations.
  
  
  RESULTS
  Hippocampal volume did not differ between FH+ participants and controls; however, relative to controls, during the memory task, FH+ participants showed increased activation in brain regions encompassing the insular cortices, putamen and pallidum as well as the dorsal anterior cingulate cortex (ACC). FH+ participants also had increased hippocampal levels of Glx.
  
  
  CONCLUSIONS
  Euthymic individuals with a parental history of depression demonstrate increased activation of hippocampal-related neural networks during a memory task, particularly in brain regions involved in processing the salience of stimuli. Changes in the activity of the ACC replicate previous findings in FH+ participants using different psychological tasks; this suggests that task-related abnormalities in the ACC may be a marker of vulnerability to depression. Increased levels of Glx in the hippocampus might also represent a risk biomarker but follow-up studies will be required to test these various possibilities.
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: Z N
authors: ZN
authors: Mannie
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: N
authors: N
authors: Filippini
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: C
authors: C
authors: Williams
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: J
authors: J
authors: Near
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: C E
authors: CE
authors: Mackay
authors: University Department of Psychiatry,Warneford Hospital, Oxford OX3 7JX,UK.
authors: P J
authors: PJ
authors: Cowen
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D003866:Depressive Disorder / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D020022:Genetic Predisposition to Disease; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D012306:Risk; D055815:Young Adult