A degenerative nerve disease is one that affects the nerves in such a way that it damages them to the point that affects the way people think. Depending on the disease, it can even affect a person’s motor skills. Essentially, degenerative nerve diseases affect the brain. Degenerative brain disorder occurs from mid to late adulthood. The results from suffering from this disease usually are in progressive (and irreversible) declines in memory and a steady regression of other abilities, mostly cognitive.