Structural plasticity of axon terminals in the adult.
There is now conclusive evidence for widespread ongoing structural plasticity of presynaptic boutons and axon side-branches in the adult brain. The plasticity complements that of postsynaptic spines, but axonal plasticity samples larger volumes of neuropil, and has a larger impact on circuit remodeling. Axons from distinct neurons exhibit unique ratios of stable (t1/2>9 months) and dynamic (t1/2 5-20 days) boutons, which persist as spatially intermingled subgroups along terminal arbors. In addition, phases of side-branch dynamics mediate larger scale remodeling guided by synaptogenesis. The plasticity is most pronounced during critical periods; its patterns and outcome are controlled by Hebbian mechanisms and intrinsic neuronal factors. Novel experience, skill learning, life-style, and age can persistently modify local circuit structure through axonal structural plasticity.
Gogolla
Nadine
N
Friedrich Miescher Institut, Maulbeerstrasse 66, CH-4058 Basel, Switzerland. nadine.gogolla@fmi.ch
Galimberti
Ivan
I
Caroni
Pico
P
D000818:Animals; D001921:Brain / Q000166:cytology*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000166:cytology*; D017729:Presynaptic Terminals / Q000502:physiology*