Understanding how brain aging outside stroke injury zones affects aphasia

After a stroke, even areas of the brain that are not directly impacted by the injury can show signs of accelerated aging. Stroke can also lead to conditions such as a language disorder called aphasia, which is highly variable among individuals in severity and treatment outlook. New in JNeurosci, Nicholas Riccardi, Leonardo Bonilha, and colleagues, from the University of South Carolina Floyd School of Medicine, advanced understanding of how brain aging in uninjured areas relates to aphasia severity and recovery following treatment. 

The researchers used an online system trained on large human brain aging datasets to measure how each person’s brain structure deviates from typical aging in individuals without stroke. In 188 people with stroke, aging differences in the side of the brain that was not directly injured by the stroke could explain aphasia severity independently of the size or location of the stroke injury. Furthermore, in patients who completed speech therapy paired with noninvasive brain stimulation, brain aging patterns measured before treatment predicted improvements in language 6 months after therapy ended. 

According to the researchers, this work provides a framework for linking normal aging models with poststroke severity and treatment success, which may be critical for informing more precise brain rehabilitation strategies.

This work suggests that recovery potential after stroke depends on the health of the rest of the brain, which is partly shaped by treatable factors like cardiovascular health. Second, because everything here came from a single routine scan and a free online tool, this could realistically reach a variety of clinical or research settings one day.”

Nicholas Riccardi, University of South Carolina Floyd School of Medicine