Diffuse Axonal Injury is also known as (DAI). It is considered one of the most common and damaging injuries found in a traumatic brain injury (head injury). This means the damage is found in a larger area in the brain instead of a focal area of the brain. It is the result of bio-mechanical "shearing" forces that happen when the head is suddenly decelerated or accelerated; this type of bio-mechanical force is found in trip/slip and falls, auto accidents, pedestrian or bicycle accidents, rear-end collisions, or sporting activities.