Concussion

The brain floats within the skull, surrounded by cerebrospinal fluid, which cushions it from the light bounces of everyday movement and the fluid may not be able to absorb the force of a sudden hard blow or a quick stop.

A violent jar or shock to the head can cause a concussion, a type of traumatic brain injury (TBI).
A concussion causes at least a temporary loss in brain function. Although losing consciousness is a common sign of a concussion, it’s possible to suffer a concussion without being completely knocked out.

Although not usually life-threatening, a concussion can have serious effects. Most people with mild injuries make a complete recovery, but it’s important to seek medical attention and to allow enough time for the healing process.

Each year, minor incidents of TBI happen to over one million people in the United States. These minor injuries result in the treatment and release from hospital emergency departments. Another 230,000 people are hospitalized each year with TBI. Of these people, 99,000 will show a lasting disability.