A system for treating medical conditions by neuromodulation of one or more target sites in the nervous system. In certain embodiments, at least one of the target sites is the medial thalamic region, including the intralaminar nucleus and the adjacent white and grey matter. In certain embodiments, where there is more than one target site, the other target sites is elsewhere in the nervous system, including the globus pallidus interna, subthalamic nucleus, corpus callosum, cerebellum, cerebral cortex (including the premotor cortex, motor cortex, and sensory cortex), ventral striatum, lateral thalamus, substantia nigra, and pedunculopontine nuclei. The medical conditions include movement disorders or improvement of movement function, stroke, neuropsychiatric or neuropsychologic disorders, neurodevelopmental disorders, and pain. Methods for treating medical conditions by neuromodulation of the intralaminar nuclei either alone or in combination with another target site(s) is also provided.