The cell biology of synaptic plasticity and neurotrophic factor has been extending to the understanding of pathological mechanisms of brain disorders. This knowledge could prove beneficial for the development of new therapies against brain diseases. Dendritic spines are actin-rich structures, which are part of most excitatory synapses in the central nervous systems. Recent studies have shown that the morphological plasticity of the spine plays a crucial role in higher brain functions, such as learning and memory. How neuronal activity modifies the morphology of the spines is an exactly prominent issue.