In an effort to discern whether cerebral vascular injuries provoke specific emotional disturbances, 20 consecutively admitted stroke patients were compared with 10 orthopaedic patients. Both groups were examined for functional disabilities (Activities of Daily Living) and for psychiatric symptoms. Reliable and valid instruments, the Hamilton Rating Scale, the Visual Analogue Mood Scale, the Present State Exam, and the Mini-Mental State Exam were employed to display the psychopathology. More of stroke patients than orthopaedic patients were depressed (45% versus 10%) even though the level of functional disability in both groups were the same. Patients with right hemisphere stroke seemed particularly vulnerable and and displayed a syndrome of irritability, loss of interest, and difficulty in concentration, in addition to depression of mood (70% of right hemisphere stroke patients versus 0% left hemisphere stroke patients and 0% orthopaedic patients). We conclude that mood disorder is a more specific complication of stroke than simply a response to the motor disability. We suggest that a controlled trial of antidepressant medication is indicated for patients with this complication.