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Medical Definition of Brain concussion
1. Transient or prolonged unconsciousness with or without impairment of higher mental functions and/or brainstem functions, due to a violent blow to the head. (12 Dec 1998)
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1. Transient or prolonged unconsciousness with or without impairment of higher mental functions and/or brainstem functions, due to a violent blow to the head. (12 Dec 1998)