Amygdala volume and verbal memory performance in schizophrenia and bipolar disorder.
OBJECTIVE
To clarify the relationship between amygdala-hippocampal volume and cognitive performance in schizophrenia and bipolar disorder.


BACKGROUND
Abnormalities of the amygdala-hippocampal complex and memory deficits have been reported in both schizophrenia and bipolar illness.


METHODS
We examined memory performance and its relationship to the volumes of the whole brain, lateral ventricles, hippocampus, and amygdala using morphometric magnetic resonance imaging in 19 patients with schizophrenia, 11 bipolar patients, and 20 healthy controls.


RESULTS
Schizophrenia patients performed more poorly than bipolar patients and controls on indices of memory functioning, whereas patients with bipolar disorder showed milder impairments relative to controls. The schizophrenia group showed reduced total cerebral volume and enlarged ventricles relative to controls, but no group differences were found for amygdala or hippocampal volume. Left amygdala volume was predictive of memory performance in both groups, correlating positively with better immediate and delayed verbal memory for bipolar patients and negatively with immediate and delayed verbal recall for schizophrenia patients. Amygdala volume was unrelated to memory performance in healthy subjects.


CONCLUSIONS
Schizophrenia and bipolar disorder both seem to be associated with anomalous and differential limbic volume-function relationships, such that the amygdala may facilitate hippocampal-dependent memory processes in bipolar disorder but impair these same processes in schizophrenia.
Department of Psychiatry, Neuroimaging Center, McLean Hospital, Harvard Medical School, Belmont, MA, USA. killgore@mclean.harvard.edu
William D S
WD
Killgore
Isabelle M
IM
Rosso
Staci A
SA
Gruber
Deborah A
DA
Yurgelun-Todd
D000328:Adult; D000679:Amygdala / Q000473:pathology*; D001245:Association Learning; D001714:Bipolar Disorder / Q000473:pathology* / Q000523:psychology*; D001921:Brain / Q000473:pathology; D002552:Cerebral Ventricles / Q000473:pathology; D005260:Female; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D011939:Mental Recall; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology; D012559:Schizophrenia / Q000473:pathology*; D012565:Schizophrenic Psychology; D013702:Temporal Lobe / Q000473:pathology; D014796:Visual Perception / Q000502:physiology