The speed at which a child’s brain matures may help forecast whether they develop depression or anxiety as teenagers, up to four years before symptoms emerge, according to the latest research.
The study analysed just under 30,000 brain scans and found that mental health conditions may stem from a disrupted developmental timeline. Published in Nature, the findings challenge long-standing assumptions about how psychiatric disorders develop.
How the brain changes during childhood
During childhood and adolescence, the cerebral cortex naturally becomes thinner as unused neural connections are pruned, helping brain function become more efficient.
Researchers at the University of Iowa and Mass General Brigham tracked children every two years from age nine. They found that cortical thinning follows a distinct wave: primary sensory regions, including the visual cortex, begin to mature at around age 13, while frontal areas linked to focus, planning and emotional regulation mature at around age 16.
When brain scans were linked with mental health surveys, children who had a thicker cortex in sensory regions at age nine were significantly more likely to experience anxiety and depression by age 13.
Possible link to development before birth
The research team found that brain regions whose cortical thickness predicted future symptoms overlapped with gene networks active in the womb. The findings indicate that early genetic development lays the groundwork for risks to adolescent mental health years later.
Experts suggest that a thicker cortex late in childhood may reflect delayed brain plasticity, which could make it harder for children to adapt to their environments.
Study cannot diagnose individual children
Scientists emphasised that the subtle patterns identified in the population-level research cannot yet be used in clinics to diagnose individual children.
Dr Avram Holmes said the work highlights the importance of considering the timing of brain development, as well as the location of brain activity, when examining psychiatric symptoms. He described the research as one of the clearest pictures yet of how the cortex develops from childhood into adolescence, but stressed that it is not sufficient by itself to predict illness outcomes for an individual child.
Source: The Independent UK
