Plasticity in somatic sensory cortex refers to the ability of cells to
change their response to sensory inputs. Typically changes depend upo
n activity-induced modifications of synaptic strength. Increasing or d
ecreasing synaptic strength is orchestrated through changes in transmi
tter release from axon terminals, in glutamate receptor properties, in
postsynaptic cell depolarization, and in calcium activation of a casc
ade of intracellular events. Synaptic changes in cortex are facilitate
d by the level of cortical excitability and modulatory transmitters th
at create the background for activity arriving over sensory pathways.
Ongoing activity initiated by peripheral receptors creates the pattern
s of activity in cortex that map the activity-dependent representation
of the body onto cortex. (C) 1997 Academic Press.