Recent evidence of the plasticity of central nervous system receptors, as well as evidence for cell-to-cell communication via the extracellular fluid (volume transmission), has been selectively reviewed. The possible relevance of those mechanisms to neurologic rehabilitation has been discussed in this speculative synthesis. A model of adaptive responses to brain damage has been proposed; it includes neuronal sprouting, synaptic receptor plasticity (unmasking), and extrasynaptic receptor plasticity (volume transmission). Key Words: Receptor plasticity-Volume transmission—Neurologic rehabilitation—Unmasking—Neurotransmit— ters-Brain plasticity.
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