Abstract: A method of preventing, alleviating or treating traumatic brain injury in an individual comprises administering to the individual a therapeutically effective and physiologically acceptable amount of an agent capable of reducing the amount of one or more aggregated forms of one or more peptides in the brain. An agent capable of reducing the amount of one or more aggregated forms of one or more peptides in the brain is suitable for use in preventing, alleviating or treating traumatic brain injury. A method for predication of the risk of an individual for complications after a traumatic brain injury comprises detecting one or more aggregated forms of one or more peptides prone to aggregate as a result of a traumatic brain injury event, in the brain of the individual, wherein an increased level of such aggregates in the brain indicates an increased risk for complications.