When most people hear the term “traumatic brain injury,” they think of something severe—coma, long hospital stays, or permanent disability. But not all brain injuries are so obvious. In fact, one of the most common forms is something called a mild traumatic brain injury, or MTBI—often referred to as a concussion.

Despite the word “mild,” this type of injury can have serious and lasting effects.

How Does a Mild Traumatic Brain Injury Happen?

A MTBI typically results from:
• A blow to the head
• A sudden jolt or whiplash (like in a car crash)
• A fall or strike during sports or a workplace accident

You do not need to lose consciousness to suffer a brain injury. Many people with concussions never pass out but still experience serious symptoms.

Medical Definition of MTBI

According to the CDC and leading brain injury specialists, a mild traumatic brain injury involves at least one of the following:
• Loss of consciousness for up to 30 minutes
• Feeling dazed, confused, or disoriented for a short time
• Memory loss about the event, lasting less than 24 hours
• A Glasgow Coma Scale score of 13 to 15 (this is how doctors assess brain function)
• Normal brain imaging (CT or MRI appears normal, even though damage may still exist)

Common Symptoms

People with MTBI may experience:
• Headache
• Dizziness or balance issues
• Nausea or vomiting
• Fatigue or sleep problems
• Trouble concentrating or remembering
• Mood changes like anxiety, irritability, or depression
• Sensitivity to light or noise