The term motor thalamus refers to a composite substructure of the ventral nuclear group of the thalamus based on connectivity and function. It includes the ventral anterior nucleus, the ventral lateral nucleus and the oral part of the ventral posterolateral nucleus. It consists of three regions: the anterolateral region of the motor thalamus, the anteromedial region of the motor thalamus and the posterior region of the motor thalamus ( Macchi-1997 ). The nomenclature of this region is extremely confusing, partly because of the number of anatomists who have independently segmented and named substructures according to different criteria and partly because reports from clinical studies in humans and neurophysiological studies in macaques use quite different nomenclatures. See Macchi-1997 and Krack-2002 for comprehensive treatment of these issues