Brain bruising, also known as a cerebral contusion, can have lasting effects for hours, days, weeks, and months after an initial injury as a result of damage to the tissue in the brain. This can include post-concussion syndrome, nerve damage, and behavioral changes, among other effects. It is important for people who experience blows to the head to receive prompt treatment for brain injury, as some complications can be prevented, reduced, or eliminated with treatment. If someone sustains a blow to the head, a neurologist should conduct an evaluation, even if the patient seems fine, as it can take hours for brain damage to occur.

It is common for people with brain bruising to have what is known as a coup-contrecoup injury. In this type of head injury, there is bruising and damage at an initial point of impact, like the area of a skull that collided with a steering wheel in an accident. There is also corresponding damage on the opposite side of the skull, caused by the brain slamming against the skull after it bounced off the initial point of impact. This can lead to widespread cognitive symptoms as two areas in the brain are involved.

When the brain is bruised, bleeding occurs in the tissues of the brain. This puts pressure on the tissue, as there is limited room for expansion inside the skull. Tissues inside the brain can be injured or killed, with damage unfolding over hours or days. A cascade of chemical reactions takes place inside the brain, leading to lasting effects after brain bruising. Prompt treatment can address some of these issues and reduce the risk of permanent damage.

After brain bruising injuries, people can experience an altered level of consciousness, seizures, headaches, behavioral changes, numbness, and tingling in the nerves, memory loss, confusion, learning disabilities, and other cognitive disabilities. Some of these changes may resolve as the patient recovers. In other cases, they can become permanent. Sometimes, they onset well after the injury; the patient may initially feel healthy, but as damage progresses inside the skull, the patient develops neurological symptoms.

In post-concussion syndrome, people experience concussion symptoms like headaches, confusion, nausea, and blurred vision for weeks or months after an initial injury. Other lasting effects after brain bruising can include the development of learning disabilities, loss of speech or other skills, and loss of coordination. Medical imaging studies may be needed to examine the brain and locate damage.