Other Opn3-eGFP+ subthalamic structures that are related to the basal ganglia, and involved in modulated motor control, include the white and gray matters of the fields of Forel, a structure implicated in epilepsy, movement and behavioral disorders (Neudorfer and Maarouf, 2018), as well as the subthalamic nucleus. The gene discussed is OPN3; the disease is epilepsy.