Fig. 3: Major pathways related to the pathogenesis of attention-deficit hyperactivity disorder (dopaminergic and serotonergic).

Dopaminergic and serotonergic neurons are primarily located respectively in the midbrain and hindbrain and control various functions. Anomalies in dopamine and/or serotonin levels contribute to the symptoms of inattention, hyperactivity, and impulsiveness in attention-deficit hyperactivity disorder (Figure inspired from the manuscript by Fontana BD et al., 2019¹⁸⁷).