1, there is a clear history of head trauma; 2, immediately after the injury, there is a brief impairment of consciousness, ranging from a few seconds to a few minutes, generally not more than 30min; 3, after the injury there is retrograde amnesia, that is, proximal amnesia; 4, at the time of injury there is pallor, pupil changes, limb relaxation, hyporeflexia, and then with the improvement of consciousness, the above symptoms gradually disappear. There is no abnormality in the neurological examination; 5.After the injury, headache, dizziness, nausea, vomiting, etc., and some may also have palpitations, tinnitus memory loss and other symptoms of plant nerve dysfunction. Note: The above clinical manifestations and a clear history of head trauma, transient impairment of consciousness immediately after the injury, and no localization signs on neurological examination are the necessary conditions for the diagnosis of concussion, which must be present at the same time and cannot be missing. The presence of retrograde amnesia is an important basis for confirming concussion. Other clinical manifestations cannot be used as the main basis for concussion diagnosis.