Spinogenesis and pruning scales across functional hierarchies.
Spinogenesis and synaptic pruning during development are widely believed to subserve connectional specificity in the mature CNS via Hebbian-type reinforcement. Refinement of neuronal circuit through this "use it or lose it" principle is considered critical for brain development. Here we demonstrate that the magnitude of spinogenesis and pruning in the basal dendritic trees of pyramidal cells differ dramatically among sensory, association, and executive cortex. Moreover, somewhat counterintuitively, we demonstrate that the dendritic trees of pyramidal cells in the primary visual area actually lose more spines than they grow following the onset of visual experience. The present findings reveal that the process of synaptic refinement differs not only according to time, but also location.
Elston
Guy N
GN
Centre for Cognitive Neuroscience, Sunshine Coast, Queensland 4562, Australia. guyelston@yahoo.com
Oga
Tomofumi
T
Fujita
Ichiro
I
D000367:Age Factors; D000818:Animals; D002452:Cell Count / Q000379:methods; D049229:Dendritic Spines / Q000502:physiology* / Q000648:ultrastructure; D008252:Macaca fascicularis; D055495:Neurogenesis / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology