This research looked at cognitive differences in people with schizophrenia, their unaffected siblings, and healthy controls. Scientists used a normative latent cognitive structure to measure how thinking patterns deviate from the norm across three specific dimensions. The goal was to understand if these structural changes happen before a person meets the full criteria for a schizophrenia diagnosis.
The results showed that cognitive heterogeneity increases from healthy controls to unaffected siblings and then to patients with schizophrenia. Specifically, reasoning remained the most common area of deviation, while processing speed declined as the condition became more severe. Unaffected siblings showed changes that were distinct from healthy controls but not always from patients.
About half of the patients had reasoning as their main area of deviation, while another third had processing speed issues. Those with processing speed problems also had higher anxiety scores. Because this was an observational study, the findings suggest a link between cognitive structure and illness risk, but they do not prove that these changes cause schizophrenia. Readers should view this as early evidence that may help guide future individualized treatments.