Impairment
It is difficult to display cases of "pure" motor memory impairment because the memory system is so widespread throughout the brain that damage is not often isolated to one specific type of memory. Likewise, diseases commonly associated with motor deficits, such as Huntington's and Parkinson's disease, have a wide variety of symptoms and associated brain damage that make it impossible to pinpoint whether or not motor memory is in fact impaired. Case studies have provided some examples of how motor memory has been implemented in patients with brain damage.
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