A concussion is a manifestation of a primary brain injury. A primary brain injury is a brain injury that occurs immediately when violence is applied to the head. Patients often misinterpret a concussion as a very serious brain injury. In fact, according to the degree and location of brain injury, there are several types of brain injury, such as concussion, brain contusion and primary brainstem injury. Concussion is one of the mildest injuries. The mechanism of its formation is still unclear, mainly intracranial pressure theory, cerebrovascular theory, cerebrospinal fluid impact theory, shear stress theory and biochemical theory. The main manifestations of concussion are as follows: 1. Disorders of consciousness: occurring immediately after head trauma, manifested as loss of consciousness or mental confusion, mostly returning within half an hour, but also up to several hours, but rarely more than 6 hours. 2, retrograde amnesia: after waking up, the situation and the injury can not be recalled, but the things before the injury can be clearly recalled. 3, autonomic dysfunction: manifested as headache, dizziness, nausea, anorexia, vomiting, tinnitus, insomnia, photophobia, inattention and unresponsiveness, etc. Gradually recovered in 3~5 days. 4. No abnormalities in cranial CT examination and no positive signs in neurological examination. A clear diagnosis can be made based on the above symptoms. 1.Patients with concussion should stay in hospital for 2-3 days after injury for short-term observation, and regularly observe the changes of consciousness, pupils and vital signs, so as to perform cranial CT examination in time to detect possible complications of intracranial hematoma. 2.Appropriate bed rest, reduce mental and physical work. 3.Symptomatic supportive treatment. Headache and insomnia can be treated with analgesics and sleeping agents respectively. If vomiting is obvious in the early post-injury period and affects feeding, intravenous fluid supplementation is recommended. 4.Spiritual encouragement, eliminate worries, do a good job of psychological medical work.