title: The contingent negative variation: some methodological problems in the recording of shifts in steady potentials.
mesh_terms: D001921:Brain / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology; D004582:Electronics, Medical; D004594:Electrophysiology / Q000295:instrumentation; D006801:Humans; D008722:Methods; D011603:Psychophysiology