These are bruises of the brain tissue. They can be very serious and potentially deadly as they can lead to brain hemorrhages. The bruise occurs when a blood vessel is damaged under the skin and they leak blood. Often they can form a large lump of blood. The danger is that blood is absorbed into spinal fluid which can cause permanent neurological damage. This leaking blood can also cause pressure to build on the brain leading to additional brain damage.Unlike a diffuse injury, such as concussion, a brain contusion is a localized brain injury. According to leading brain injury studies, brain contusions are present in twenty to thirty percent of severe brain injuries.Symptoms of brain contusion can include weakness, numbness, difficulty with coordination, memory, and/or cognitive problems.