Childhood Cognitive Problems may Foreshadow Schizophrenia Diagnosis in Adulthood

verbal reasoning, working memory, attention and processing speed, a finding that may increase researchers’ understanding of how schizophrenia develops.

co-authors Terrie E. Moffitt, professor of psychology and neuroscience at Duke, and Richard Keefe, director of Duke's Schizophrenia Research Group—found that, for each year between age 7 and 13 years, children who later received a diagnosis of schizophrenia lost between 0.17 and 0.26 years in mental age, compared with children who were not later diagnosed with the mental illness. The researchers also observed two patterns: the children who later developed schizophrenia showed early deficits in verbal and visual learning, as well as reasoning and conceptualization, which stayed with the children as they aged; those in the group also exhibited slower development than their peers in processing speed, attention, visual-spatial problem solving, and working memory.

The research team—led by study

The long-term study examined more than 1,000 New Zealanders born from 1972 to 1973. Based on whether the children developed schizophrenia as adults, the researchers were able to look back at the child’s early school years and track the progress of cognitive deficits as the participants were tested every other year from age 3-13 years. By age 32, “1 percent of the study participants met the formal criteria for schizophrenia and had been hospitalized and put on antipsychotic medication,” while “another 2.5 percent met the diagnostic criteria for the disorder, but hadn't received treatment,” according to the researchers.

"The proportion of kids who don't score well on these tests is big, and the number of kids who develop schizophrenia is tiny," said Moffitt. However, now that participants are in their late 30s and, for some, mental illnesses have been identified, "we looked backwards to understand more about how schizophrenia may develop."

The American Journal of Psychiatry.

Results of the study were published in

Duke University researchers have discovered that adults with schizophrenia may exhibit a pattern during childhood of cognitive problems, including difficulties with