Associations between neurological soft signs, executive functions, and brain-derived neurotrophic factor in boys with attention-deficit hyperactivity disorder.

Background: To determine the association between neurological soft signs, executive functions, and serum brain-derived neurotrophic factor (BDNF) levels in children with attention-deficit hyperactivity disorder (ADHD). Methods: Serum BDNF levels were measured in 87 drug-naive boys with ADHD, aged 7--12 years. The Revised Physical and Neurological Examination for Subtle Signs for neurological soft signs, Stroop Color-Word Test for attention functions, and Judgment of Line Orientation Test (JLOT) for visuospatial abilities were performed. Results: Age correlated negatively with dysrhythmia, total time, and total overflow in timed movements, Stroop Color-Word Time (SCWT), and serum BDNF levels. The JLOT significantly negatively correlated with Total Gaits and Stations (P1) and Total Time in Timed Movements (adjusted R2 = 0.247). In addition, SCWT maintained a significant correlation with Total Overflow in Timed Movements (adjusted R2 = 0.206). There was no correlation between serum BDNF levels and NSS. Conclusion: The association between NSS, visuospatial abilities, and selective attention may express a maturational delay in ADHD pathophysiology. Moreover, BDNF may play a role in this maturational delay. Future studies should investigate the contribution of BDNF to neuronal maturation in ADHD. [ABSTRACT FROM AUTHOR]