Editorial: Exciting Dendritic Spines

The ability of a synapse to alter its strength based on use (synaptic plasticity) reigns as the basis of most cellular models of learning and memory [1]. However, if synaptic plasticity is king, then the dendritic spine is its kingdom. The dendritic spine, which houses the majority of excitatory synapses in the mammalian central nervous system, also undergoes dynamic changes to its shape (structural plasticity) in an activity-dependent manner. Indeed, strengthening of the synapse, or long-term potentiation (LTP), is often associated with spine head enlargement, whereas weakening of the synapse, or long-term depression (LTD), is often associated with spine head shrinkage. Underlying structural plasticity is the cytoskeleton protein, actin, whose dynamics and organization ultimately shape spine morphology, and which can also influence synaptic plasticity through modulation of membrane receptor insertion, removal and function. Thus, actin is both governed by and governs the king and kingdom. This special issue of The Open Neuroscience Journal explores many different aspects of dendritic spine morphology, regulation and function in health and disease.