Researchers from the University of Seville have mapped potential origins of structural brain damage in individuals with schizophrenia spectrum disorders (SSDs). The study focused on regions that show significant morphological changes during the early stages of SSDs when compared to neurotypical individuals matched for sex and age.
The research supports existing hypotheses suggesting that psychiatric conditions may begin as localized structural alterations in the brain. These initial changes are thought to spread to other areas via brain connectivity, leading to a pattern of disconnection within certain networks. In SSDs, this process is marked by atypical brain development, including reduced volume, area, and thickness in the cerebral cortex. Such alterations are linked to cognitive deficits and severe symptoms.
To investigate these patterns, scientists used Morphometric Inverse Divergence (MIND) networks. This methodology relies on data from structural magnetic resonance imaging (MRI) — specifically volume, surface area, and cortical thickness — to estimate how similar different cortical regions are structurally. Lower MIND values suggest greater morphological disconnection between paired regions.
The team constructed MIND networks for 195 healthy controls and 352 individuals diagnosed with SSDs. Results indicated that those with SSDs had significantly lower structural similarity in several brain regions, especially the temporal, cingulate, and insular lobes. Reductions were more pronounced among patients with more severe clinical symptoms or greater cognitive impairment. Most alterations appeared in higher-order association areas—regions crucial for complex cognitive functions that mature later than other parts of the brain.
The study also identified specific "epicentres" where early-stage structural damage was most pronounced relative to what would be expected for neurotypical peers.
In addition, researchers analyzed 46 neurobiological characteristics related to the MIND networks. They found that areas showing less similarity in people with SSDs tended to have higher concentrations of astrocytes and neurotransmitters such as dopamine and serotonin but displayed reduced metabolism and diminished cortical microstructure.
According to the research team: "These findings provide evidence of the complex interaction between structural similarity, maturation processes and underlying neurobiology in determining the clinical status of individuals with SSD." They added: "This approach could contribute to the development of structural biomarkers and personalised therapeutic strategies based on each patient's biological and clinical profile."
