Removing Brakes on Adult Brain Plasticity: From Molecular to Behavioral Interventions

Department of Brain and Cognitive Sciences, University of Rochester, Rochester New York 14627-0268, USA.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 11/2010; 30(45):14964-71. DOI: 10.1523/JNEUROSCI.4812-10.2010
Source: PubMed


Adult brain plasticity, although possible, remains more restricted in scope than during development. Here, we address conditions under which circuit rewiring may be facilitated in the mature brain. At a cellular and molecular level, adult plasticity is actively limited. Some of these "brakes" are structural, such as perineuronal nets or myelin, which inhibit neurite outgrowth. Others are functional, acting directly upon excitatory-inhibitory balance within local circuits. Plasticity in adulthood can be induced either by lifting these brakes through invasive interventions or by exploiting endogenous permissive factors, such as neuromodulators. Using the amblyopic visual system as a model, we discuss genetic, pharmacological, and environmental removal of brakes to enable recovery of vision in adult rodents. Although these mechanisms remain largely uncharted in the human, we consider how they may provide a biological foundation for the remarkable increase in plasticity after action video game play by amblyopic subjects.

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Available from: Dennis M Levi, Oct 10, 2015
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    • "etworks and more extensive hard wiring of existing circuits ( Hensch , 2005 ) . Most importantly , invasive or noninvasive ( e . g . , pharmacological ) interventions resulting in decreased strength of certain inhibitory inputs were recently successfully used to enhance experience dependent neuronal plasticity in adult nervous system ( reviewed in Bavelier et al . , 2010 ) . Changes in inhibition were proposed to be particularly important for neuronal plasticity following sensory experience . It has been show that in the adult primary auditory cortex , the dynamics of synaptic receptive field plasticity is associated with a reduction of synaptic inhibition which was followed by a large increase in excit"
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