A cerebral laceration is a form of a brain injury that occurs many times in what we call a closed head injury where the skull wasn't penetrated. When a person falls or they are involved in some type of accident where they strike their head or they don't strike their head but their head was violently shaken from front to back, like in a whiplash type motion, and it's the movement of the brain within the skull that stretches the brain fibers and actually tears the blood vessels that connect the areas of the brain. When something like this happens, bleeding occurs and when you have bleeding, the body's response is to rush more blood to the area which creates swelling. The swelling of the brain tissue is what causes this type of injury.
Many times after someone is involved in an accident, they'll have symptoms such as dizziness, nausea, vomiting, loss of consciousness, speech issues and this might be an indication of the presence of a cerebral laceration because of the swelling of the brain tissue. It's considered an emergency condition and that's why when someone reports to the emergency room with any of these symptoms they're generally going to order a CT scan, which is a series of x-rays that are specifically designed to identify the presence of blood in the brain which is indirect evidence of this type of injury.