Study reveals brain changes associated with ADHD remission

A recent study published in NeuroImage: Clinical used state-of-the-art neuroimaging techniques to determine which brain changes may cause remission in childhood ADHD. Christienne Damatac and colleagues observed brain changes in those diagnosed with ADHD over 16 years. Their findings suggest that the improved symptoms of hyperactivity and inattention are the result of increased white matter density in an area of ​​the brain known as the left corticospinal tract. Additionally, reduced ADHD symptoms were associated with more neural connections in the same region.

ADHD is a common diagnosis in childhood. However, some are fortunate enough to outgrow challenging symptoms into adulthood, while others never do. Understanding why this is so may lead to important innovations in the treatment of the disorder. One hypothesis is that the malfunctioning parts of the brain that result in ADHD symptoms can never repair themselves. Instead, for some, as the brain develops, other regions take over responsibilities for damaged areas. Damatac and colleagues were curious if this was the case and if these changes would persist over time.

Fifty-five people diagnosed with ADHD in the experimental condition were examined four times over 16 years. The neuroimaging techniques used are known as diffusion tensor imaging, diffusion-weighted imaging and fixel-based imaging. At the time of the first scans, the participants were between 6 and 18 years old.

The research team found that as their subjects aged, those who went into remission from ADHD experienced changes in white matter that were not seen in those who did not go into remission and healthy controls without ADHD. Moreover, these brain differences persisted into adulthood.

Brain changes like those found here are thought to be the result of experience. For example, if an individual becomes blind and then learns to read braille, the brain will change in response to this new and necessary skill. In addition, areas of the brain that were once responsible for processing vision can take over other jobs to help a blind person navigate the world. These findings from this study indicate that as the brains of individuals with ADHD mature, some individuals may repeatedly engage in symptom-compensating strategies. These repetitive behaviors can result in brain changes seen in those who have gone into remission.

For children with ADHD, this research implies that remission is possible if strategies that help compensate for deficits are practiced frequently. Furthermore, it is suggested that investing in support in the school environment and educating parents about strategies could help pave the way to long-term remission.

Damatac and team acknowledge that their imaging techniques have changed over time, which may have had unknown consequences for the data. Second, some of the original participants dropped out, and those who remained may not be as representative as the original sample. Finally, the sample size was too small to assert cause and effect; there may be other factors that led to persistent ADHD.

In addition to these limitations, this research provides neurological evidence that consistent use of coping strategies for ADHD symptoms may be helpful. Findings like this will surely be used to better fund and educate those who help children with ADHD.

The study, “Longitudinal changes in ADHD symptoms in relation to white matter microstructure: a tract-specific fixelle-based analysis“, the authors are Christienne Damatac, Sourena Soheili-Nezhad, Guilherme Blazquez Freches, Marcel Zwiers, Sanne de Bruijn, Seyma Ikde, Christel M. Portengen, Amy Abelmann, Janneke Dammers, Daan van Rooij, Sophie Akkermans, Jilly Naaijen, Barbara Franke, Jan Buitelaa, Christian Beckmann and Emma Sprooten.