Electrophysiological responses (changes in brain voltage) that can be tied to exposure to specific stimuli, as measured via EEG (see “Electroencephalography (EEG)”). The term is also commonly used to refer to the measurement technique and/or specific analysis used to capture and interpret the data. They are used in neuroscience research to capture responses to stimuli that may be unobservable in standard behavioral and/or self-report methods. See “Biometrics.”