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dementia – n. a term for diseases and conditions characterized by a loss of memory, language, problem-solving and other thinking skills. Alzheimer's is the most common cause of dementia.
focus – v. to direct your attention or effort at something specific
benefits – n. good or helpful results or effects
participation – n. the act of joining with others in doing something
concussion – n. an injury to the brain that is caused by something hitting the head very hard
