Brain structure changes visualized in early- and late-onset blind subjects.
We examined 3D patterns of volume differences in the brain associated with blindness, in subjects grouped according to early and late onset. Using tensor-based morphometry, we mapped volume reductions and gains in 16 early-onset (EB) and 16 late-onset (LB) blind adults (onset <5 and >14 years old, respectively) relative to 16 matched sighted controls. Each subject's structural MRI was fluidly registered to a common template. Anatomical differences between groups were mapped based on statistical analysis of the resulting deformation fields revealing profound deficits in primary and secondary visual cortices for both blind groups. Regions outside the occipital lobe showed significant hypertrophy, suggesting widespread compensatory adaptations. EBs but not LBs showed deficits in the splenium and the isthmus. Gains in the non-occipital white matter were more widespread in the EBs. These differences may reflect regional alterations in late neurodevelopmental processes, such as myelination, that continue into adulthood.
Leporé
Natasha
N
Laboratory of Neuro Imaging, Department of Neurology, David Geffen School of Medicine at UCLA, University of California-Los Angeles, 635 Charles E. Young Drive South, Los Angeles, CA 90095, USA. nlepore@loni.ucla.edu
Voss
Patrice
P
Lepore
Franco
F
Chou
Yi-Yu
YY
Fortin
Madeleine
M
Gougoux
Frédéric
F
Lee
Agatha D
AD
Brun
Caroline
C
Lassonde
Maryse
M
Madsen
Sarah K
SK
Toga
Arthur W
AW
Thompson
Paul M
PM
D000328:Adult; D017668:Age of Onset; D000465:Algorithms; D001766:Blindness / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D003337:Corpus Callosum / Q000473:pathology; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000473:pathology; D055815:Young Adult