Neuropathology is a specialty within the study of pathology focused on the disease of the brain, spinal cord, and neural tissue.[26] This includes the central nervous system and the peripheral nervous system. Tissue analysis comes from either surgical biopsies or post mortem autopsies. Common tissue samples include muscle fibers and nervous tissue.[27][failed verification] Common applications of neuropathology include studying samples of tissue in patients who have Parkinson’s disease, Alzheimer’s disease, dementia, Huntington’s disease, amyotrophic lateral sclerosis, mitochondria disease, and any disorder that has neural deterioration in the brain or spinal cord.[28