Accelerated brain aging was associated with dementia, addiction, and psychiatric disorders such as schizophrenia. Researchers estimate brain age using predictive age difference (PAD), which compares a person’s chronological age with the age predicted from brain imaging. Dementia shows the widest brain age gapAlzheimer’s disease and mild cognitive impairment had the strongest associations with elevated PAD, indicating the largest gaps between predicted brain age and chronological age. Elevated PAD appeared in the prefrontal cortex across multiple brain disorders. Even with those limitations, the researchers suggest that further study of PAD could support the development of biomarkers for common brain disorders.