In the long term after traumatic brain injury, the most disabling problems are generally related to neuropsychiatric sequelae, including personality change and cognitive impairment, rather than neurophysical sequelae. Cognitive impairment after severe injury is likely to include impaired speed of information processing, poor memory and executive problems. Personality change may include poor motivation, and a tendency to be self-centred and less aware of the needs of others. Patients may be described as lazy and thoughtless. Some become disinhibited and rude. Agitation and aggression can be very difficult to manage. Anxiety and depression symptoms are quite frequent and play a role in the development of persistent post-concussion syndrome after milder injury. Depression may be associated with a deterioration in disability over time after injury. Psychosis is not unusual though it has been difficult to confirm that traumatic brain injury is a cause of schizophrenia. Head injury may, many years later, increase the risk of Alzheimer's disease. Good rehabilitation probably minimizes the risk of psychiatric sequelae, but specific psychological and pharmacological treatments may be needed.