Menu Healthy Lifestyle Diseases & Conditions First Aid Symptoms Tests & Procedures Videos Definitions FAQs ConcussionUpdated: 2017-06-13OverviewA concussion is a brain injury caused by a blow to the head or a violent shaking.SymptomsSymptoms may be mild and subtle, but headaches, memory loss, and confusion are common. Repeated vomiting and some symptoms may require emergency care. Concussions in infants and toddlers can be difficult to recognize.TreatmentsRest is the most appropriate treatment. © 1998-2022 Mayo Foundation for Medical Education and Research(MFMER). All rights reserved. Terms of Use