Reduced basal forebrain and hippocampal activation during memory encoding in girls with fragile X syndrome.
Fragile X syndrome (FraX), the most common heritable cause of developmental disability, is associated with IQ, memory, and visuospatial processing deficits. The fragile X gene (FMR1) is prominently transcribed in two regions critical to memory encoding and attention: the hippocampus and the basal forebrain. To probe functional MRI activation abnormalities associated with the disorder, girls with FraX and age-matched, normally-developing girls were scanned during a test of visual memory encoding. While there were considerable similarities in activation patterns between the two groups, the girls with FraX showed significantly less activation in the hippocampus and the basal forebrain. This is the first study, to our knowledge, demonstrating functional deficits in FraX subjects in brain regions known to have the highest FMR1 transcription.
Greicius
Michael D
MD
Department of Neurology and Neurological Sciences, Stanford Brain Research Institute, Stanford University School of Medicine, Stanford, CA 94305, USA.
Boyett-Anderson
Jesse M
JM
Menon
Vinod
V
Reiss
Allan L
AL
D000293:Adolescent; D000328:Adult; D000368:Aged; D001931:Brain Mapping; D000077463:Carbamide Peroxide; D016022:Case-Control Studies; D002648:Child; D003071:Cognition; D004338:Drug Combinations; D005260:Female; D005600:Fragile X Syndrome / Q000473:pathology / Q000503:physiopathology*; D006624:Hippocampus / Q000098:blood supply / Q000503:physiopathology*; D006801:Humans; D007360:Intelligence; D008279:Magnetic Resonance Imaging / Q000379:methods; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010545:Peroxides / Q000097:blood; D016548:Prosencephalon / Q000098:blood supply / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology; D014508:Urea / Q000031:analogs & derivatives* / Q000097:blood; D014888:Wechsler Scales
D004338:Drug Combinations; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea