Abstract… once the development was ended, the founts of growth and regeneration of the
axons and dendrites dried up irrevocably. Santiago Ramón y Cajal Cajal's neurotropic
theory postulates that the complexity of the nervous system arises from the collaboration of
neurotropic signals from neuronal and non-neuronal cells and that once development has
ended, a paucity of neurotropic signals means that the pathways of the central nervous
system are “fixed, ended, immutable”. While the capacity for regeneration and plasticity of …