An event-related potential, or ERP, is a brain response taken from an electroencephalography (EEG) signal that occurs in response to a particular event. ERPs are examined in studies that want to look at how the brain responds to a stimulus rather than exploratory studies that aim to examine broad patterns of neural activity. ERPs are obtained by grouping together all EEG signals that are time-locked to the onset of a stimulus, segmenting these portions of EEG data from the rest of the data, and averaging them together to reduce noise and provide a picture of the most consistent brain response to the event. Particular ERPs have been shown to indicate certain perceptions or processes; for instance, a negative response around 150-250ms post-stimulus onset often indicates the perception of an oddball auditory stimulus (Näätänen et al., 2007). ERPs thus prove useful in studying rhythmic cognition, because they can reveal the neural response to specific auditory events.