Published: 21-01-2013 00:00 | Updated: 08-06-2015 11:17

Decline in verbal ability in adolescence linked to psychosis

New research from Karolinska Institutet and King's College London's Institute of Psychiatry has found that adolescents whose verbal performance drops off are at increased risk of developing schizophrenia and other psychotic disorders many years later. The findings are published in the scientific periodical JAMA Psychiatry.

Clear evidence from many prospective population-based studies indicates that patients who develop psychosis in adulthood experienced various cognitive deficits during childhood and adolescence. However until now it had been unclear whether these deficits become more severe during adolescence.

The current article, a population-based cohort study in Swedish males, tested cognitive functioning at age 13 and 18 using standardised tests. The researchers found that a relative decline in verbal ability between age 13 and 18 was associated with increased risk of hospitalization for schizophrenia and other psychotic disorders in adulthood.

Decline in verbal score between ages 13 and 18 was a much stronger predictor of later psychosis than the score at age 18 alone. However, the researchers point out that a decline in verbal ability in adolescence can't be used to predict with any degree of certainty whether a particular individual will develop psychosis.

"We know that the brain undergoes a rapid period of development during adolescence, and these findings add to the evidence that brain development may be atypical in some people who later develop psychosis", says Christina Dalman, researcher at the Department of Public Health Sciences of Karolinska Institutet.

The study was funded by the Swedish Research Council for Working Life and Social Research and the NIHR Biomedical Research Centre for Mental Health at the South London. Much of this news article has originally been published as a press release from King's College London.


Decline in cognitive performance between ages 13 and 18 years and the risk for psychosis in adulthood: a Swedish longitudinal cohort study in males.
MacCabe J, Wicks S, Löfving S, David A, Berndtsson �, Gustafsson J, et al
JAMA Psychiatry 2013 Mar;70(3):261-70