If someone is brain damaged they are unable to look after their own affairs and are said to be under a mental disability. They do not have the necessary capacity to act by themselves.
The individual will need to be assessed by a Doctor and they will be classified as a Patient under the Mental Health Act.
In these circumstances the individual will not be in a position to provide us with instructions. As such a Litigation Friend will be appointed. The Litigation Friend will have all the burdens of running the Litigation but any compensation that is achieved will be for the benefit of the injured party.