Identical neural risk factors predict cognitive deficit in dyslexia and schizophrenia.

In previous work, the authors found that an anatomical risk index created from the combination of 7 neuroanatomical measures predicted reading and oral language skills in individuals with learning disabilities. Individuals with small auditory brain structures and reduced asymmetry had more deficits than those with large structures and exaggerated asymmetry. In the present study, the same anatomical index predicted reading and other cognitive abilities in 45 individuals with chronic schizophrenia. The anatomical risk index was significantly associated with broad cognitive ability (Pearson r = .53, p < .0001), reading comprehension (r = .58, p < .0001), and a measure of nonverbal reasoning (r = .39, p < .01), but not with age, parental socioeconomic status, symptom measures, alcohol use, or processing speed. These findings support the prediction that reduced size and asymmetry in temporal lobe auditory cortex and cerebellum may not be specific risk factors for schizophrenia but for cognitive deficits that characterize a broad spectrum of developmental disorders.