A series of 261 patients was followed up six months to six years after a subarachnoid haemorrhage. Personality change, assessed largely from the statements of other informants showed overall impairment in 41 per cent (mild in 22 per cent, moderate in 15 per cent and severe in 4 per cent). Personality improvement, apparently due to a leucotomy effect, was found in 5 per cent.
Personality impairment was largely proportional to the amount of brain damage, as indicated by CNS signs, and was most common in patients with middle cerebral artery aneurysms.
The commonest change was an increase in anxiety and irritability with loss of vitality and was correlated with brain damage at any site. The existence of the classical frontal lobe syndrome was confirmed. Patients with anterior communicating artery aneurysms (and probably frontal lobe damage) more often had personality change without intellectual impairment. Scores on the Benton Visual Retention Test and a modified Inglis Paired Associate Test were highly correlated with the presence of personality impairment but did not distinguish the mildly from the moderately impaired.
The method of study, relying largely on the statements of other informants and largely excluding affective symptoms from consideration, minimized the importance of previous personality.