Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Lewy Body Disease ?
    ### Response:
    Lewy body disease is one of the most common causes of dementia in the elderly. Dementia is the loss of mental functions severe enough to affect normal activities and relationships. Lewy body disease happens when abnormal structures, called Lewy bodies, build up in areas of the brain.
    