Neurophysiological atlas created by mapping of clinical responses elicited on electrical stimulation of the human thalamus.

By computer processing of intraoperative neurophysiological data and intraoperative X-ray films, and using a 0.5-mm-step three-dimensional atlas created by interpolation of Schaltenbrand-Bailey's atlas, a neurophysiological atlas based on clinical responses upon electrical stimulation of the subcortical structures of patients who underwent stereotactic surgery in the awake state was created. There was considerable overlap in the distribution of motor and sensory responses in the vicinity of the ventral intermediate (VIM) thalamus: however, motor responses, particularly irregular movements, tended to be confined within the VIM and ventro-oralis posterior (VOP), whereas sensory responses tended to be localized in the VIM and ventroposterolateral nuclei, with considerable extension into the ventroposterior subthalamic region. In either motor or sensory responses, no definite somatotopic pattern could be determined.