Under the Mental Capacity Act 2005, a patient who is unable to take a decision for himself in relation to medical treatment because of an impairment of, or a disturbance in the functioning of, the mind or brain. This would include a person with certain forms of mental illness or with significant learning difficulties as well as a person who is suffering from temporary concussion or loss of consciousness. Unless there is in existence a valid and applicable advance decision or a lasting power of attorney, the decision how and whether to treat an incompetent patient will be made by the relevant medical professional in accordance with what he considers to be in that patient's best interest. In certain cases, for example where a patient is in a persistent vegetative state or in the event of a dispute, the decision will be made by the courts, who also have the power to appoint a deputy. Compare competent patient.