CT HEAD ANATOMY Axial slice of a non contrast CT head at the level of the basal ganglia 👨🏽‍💻The basal ganglia are a group of structures including the caudate and lentiform nucleus in the cerebrum as seen here, the substantia nigra within the midbrain and the subthalamic nuclei in the diencephalon 👨🏽‍💻Simply put the basal ganglia is important in motor function, facilitating movement and inhibiting competing movements. It is depletion of dopaminergic neurons within the substantia nigra that