The researchers looked at groups of boys born in 1953, 1967, 1972, and 1977. All the boys were given tests of verbal, spatial, and inductive ability at age 13 and again at age 18, when drafted into the army. Compared with unaffected young men, those who later developed psychoses had a relative decline in verbal ability over the testing period, said James McCabe, Ph.D., of King’s College, London and colleagues, writing online in JAMA Psychiatry.
“Decline between ages 13 and 18 years was a much stronger predictor of psychosis than the verbal ability score at age 18 years alone,” they said. “This suggests an impairment of late neurodevelopment affecting the acquisition of verbal skills in adolescent boys and young men who later develop psychosis."
To read more about prevention of psychosis, see Psychiatric News here and here.