Concussion

concussion is a temporary, brief change in mental function without damage to the structure of the brain. Often, people lose consciousness briefly (usually a few minutes or less), but they may simply become confused or be unable to recall events and experiences (amnesia) that occurred shortly before or soon after the injury

Adult hispanic business man over isolated background with hand on head for pain in head be
Symptoms typically include: 
 
Headache dizziness, fatigue, poor memory, inability to concentrate, trouble sleeping, difficulty thinking, irritability, depression, and anxiety. These symptoms are  called the post-concussion syndrome.

 
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