A procedure in which a neurosurgeon uses a macroelectrode to stimulate, or activate, specific neuron clusters to confirm their functions. Different structures in the brain, such as the pallidum, subthalamic nucleus (STN), and the thalamus, produce unique patterns of electrical activity. The neurosurgeon uses the responses from macroelectrode stimulation to make sure microelectrodes are in correct position during surgeries such as pallidotomy, thalamotomy, and deep brain stimulation (DBS). During these surgeries the person is sedated but awake, so he or she can respond to instructions from the neurosurgeon and provide additional information about any sensations that macroelectrode stimulation produces. Macroelectrode stimulation is painless, although it sometimes evokes responses such as perception of particular tastes or smells or movement of a part of the body. These responses help the neurosurgeon create a map of the brain’s functional areas.