All living organisms have an inherent capacity and ability to self-organize throughoutlife, and organizational processes affecting all systems are reflective of the organisms history(including experience and use). Following an acute brain lesion, ischemic, traumatic, orhypoxic, those individuals who do not die begin to demonstrate behavioral recovery, and theunderlying biological manifestations of recovery reflect the inherent reorganization ability of the central nervous system. The concept of the brain as plastic and adaptable is nowadaysaccepted in the clinical community. Many studies have demonstrated chemical and anatomicplasticity in the cerebral cortex of adult animals. Animals reared or housed as adults incomplex environments with access to various toys and activities develop more dendriticbranching and more,synapses per neuron and have higher gene expression for trophicfactors than animals housed individually or m small groups in standard cages.