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stereoelectroencephalography ster·e·o·e·lec·tro·en·ceph·a·log·ra·phy (stěr'ē-ō-ĭ-lěk'trō-ěn-sěf'ə-lŏg'rə-fē, stēr'-)n. The recording of electrical activity in three planes of the brain by means of surface and depth electrodes.