Which of these is a result of a direct blow to the head?
Concussion, also known as mild traumatic brain injury (mTBI), is typically defined as a head injury that temporarily affects brain functioning. Symptoms may include loss of consciousness (LOC); memory loss; headaches; difficulty with thinking, concentration or balance; nausea; blurred vision; sleep disturbances; and mood changes. Any of these symptoms may begin immediately, or appear days after the injury, and it is not unusual for symptoms to last four weeks. Fewer than 10% of sports-related concussions among children are associated with loss of consciousness.
Common causes include motor vehicle collisions, falls, sports injuries and bicycle accidents. The mechanism may involve either a direct blow to the head or forces elsewhere on the body that are transmitted to the head.