National Institutes of Health concussion http://www.nlm.nih.gov/medlineplus/ency/article/000799.htm MedlinePlus: Concussion concussions MedlinePlus: Concussion U.S. National Library of Medicine U.S. National Library of Medicine National Institutes of Health National Institutes of Health National Institutes of Health www.nlm.nih.gov/medlineplus/ concussion https://www.nlm.nih.gov/medlineplus/ency/article/000799.htm concussion concussions include A concussion National Institutes of Health concussion MedlinePlus: Concussion U.S. National Institutes of Health Full article >>> A concussion National Institutes of Health www.nlm.nih.gov/medlineplus/ency/article/000799.htm http://www.nlm.nih.gov/medlineplus/ency/article/000799.htm U.S. National Institutes of Health National Institutes of Health MedlinePlus ieraksts http://www.nlm.nih.gov/medlineplus/ency/article/000799.htm concussion