Use-dependent inhibition of dendritic spines.

Dendritic spines are now known to be subject to use-dependent plasticity that affects both their structure and their numbers. Recently, it has been demonstrated that a use-dependent increase in the density of dendritic spines occurs in both excitatory and inhibitory synapses in the mouse barrel cortex. Furthermore, it has been shown that although this increase in the density of spines and excitatory synapses is transient, the increase in spinous inhibitory synapses is long-lasting. These findings lend further support to the hypothesis that synapses in the mature cortex are subject to continual use-dependent plasticity.