This book "Neuroplasticity and its Dark Sides" stresses some less well-known aspects of neuroplasticity, namely that are two kinds of neuroplasticity, one that is beneficial to the individual and one that is harmful. Activation of neuroplasticity is important for learning new skills and adapting to changing demands but neuroplasticity can also create symptoms and signs of common and widespread diseases such as chronic neuropathic pain and severe tinnitus. Spasticity and some forms of spasm are also caused by such maladaptive neuroplasticity, plasticity disorders. Plastic changes also play important roles in many other disorders. This is the dark side of neuroplasticity. Understanding the dark sides of neuroplasticity is important for treatment of many common disorders. For example, reversing such bad plastic changes would be an ideal treatment if it could be done effectively and with little adverse side effects. The book also describes the pathophysiology of some common neurological disorders where expression of neuroplasticity is evident or where it may play a role in producing the symptoms. Three appendices provides the anatomical and physiological bases for The book discusses how activation of neuroplasticity can cause symptoms of diseases and it provides a comprehensive description of the basis for neuroplasticity in general. The roles of the ability to change the efficacy of synapses and change in protein synthesis are discussed in detail. The book discusses another less well-understood property of neuroplasticity, namely that not all brain systems are plastic. The fact that attempts to change sexual preferences have been generally unsuccessful indicates that the function of some neural circuits in the brain cannot be changed or are difficult to change, which means that some circuits are "hard-wired." Personalities have shown difficult to change thus indicating that some very complex circuitry in the brain may be less plastic than normally assumed. Long-term memory is another example of brain circuits that are difficult to change. Failed success in treatment of posttraumatic stress syndrome (PTSD) shows that some memory functions are difficult to change. Understanding of neuroplasticity can benefit diagnosis and treatment of many disorders of the nervous system. The results of basic neuroscience studies of neuroplasticity are fundamental for the understanding the normal as well as many forms of abnormal function of the central nervous system. Up-to-date information about the pathophysiology of disorders where neuroplasticity is a factor can provide better treatment of many diseases. This book promotes the use of knowledge about neuroplasticity in diagnosis and treatment of disorders of the nervous system.