Thick visual cortex in the early blind.
We investigated the key neurodevelopmental factors that determine cortical thickness, namely synaptogenesis and regression, by analyzing the thickness of the visual cortex in humans with early- and late-onset blindness. The bilateral visual cortices of the early blind were significantly thicker than those of the late blind and the sighted controls, but the latter two groups did not differ significantly. This suggests reduced "pruning" of synapses in the visual cortex, which may be due to a lack of visual experience during a critical developmental period. These findings support the hypothesis that sensory experience is necessary for an appropriate regression and remodeling of neuronal processes and that synaptic regression might be a major determinant of macroscopic anatomical features like cortical thickness.
Jiang
Jiefeng
J
LIAMA Center for Computational Medicine, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China.
Zhu
Wanlin
W
Shi
Feng
F
Liu
Yong
Y
Li
Jun
J
Qin
Wen
W
Li
Kuncheng
K
Yu
Chunshui
C
Jiang
Tianzi
T
D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D001766:Blindness / Q000473:pathology* / Q000503:physiopathology; D001931:Brain Mapping; D002454:Cell Differentiation / Q000502:physiology; D049229:Dendritic Spines / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology*; D017729:Presynaptic Terminals / Q000473:pathology; D012683:Sensory Deprivation / Q000502:physiology*; D013569:Synapses / Q000473:pathology*; D013997:Time Factors; D014793:Visual Cortex / Q000166:cytology / Q000254:growth & development* / Q000473:pathology*; D014795:Visual Pathways / Q000166:cytology / Q000254:growth & development / Q000473:pathology; D055815:Young Adult