Brain maps based on magnetic resonance imaging (MRI) scans showing grey matter loss in the brains of patients with very early-onset schizophrenia (right) compared to healthy adolescents (left). The data are annual averages of 12 healthy and 12 schizophrenic subjects over 5 years between the ages of 13 and 18. There is profound, progressive grey matter loss in the schizophrenic subjects. The loss of grey matter volume may be the cause of some symptoms of schizophrenia, including thought disorder and hallucinations.