Cerebral atrophy in young cannabis smokers.

Evidence of cerebral atrophy was demonstrated by air encephalography in ten patients with histories of consistent cannabis smoking over a period of 3-11 years. The average age of the patients was 22 years; all were males. Amphetamines and lysergide (L.S.D.) had also been taken, but in much smaller amounts. Measurements of the lateral and third ventricles were significantly different from those in thirteen controls of a similar age-group.