Results and Conclusion from the study:

> Results Clinical improvement in HI symptoms over time was associated with more fiber density at follow-up in the left corticospinal tract (lCST) (tmax = 1.092, standardized effect[SE] = 0.044, pFWE = 0.016). Improvement in combined ADHD symptoms over time was associated with more fiber cross-section at follow-up in the lCST (tmax = 3.775, SE = 0.051, pFWE = 0.019).

> Conclusions Aberrant white matter development involves both lCST micro- and macrostructural alterations, and its path may be moderated by preceding symptom trajectory.