The Recording and Quantification of Event-Related Potentials: I. Stimulus Presentation and Data Acquisition

Abstract

Event-related potentials (ERPs) are the changes in the ongoing electrical activity of the brain (the EEG) that are elicited by either an external physical stimulus or an internal psychological “event”. This article provides a tutorial review of the methods used for the collection of ERP data. Because ERPs are influenced by both stimulus parameters and the mental state of the subject (what the subject is “doing”), precise control over how the stimulus is presented and how the subject’s response is monitored must be described. ERPs are generally recorded from electrodes placed on the scalp. How the electrodes are placed (the montage) and the choice of the reference to which the electrical activity of the scalp are compared will have a large influence on the results. Electrodes will also pick up extraneous artifact or “noise”. Methods to reduce this noise are described. ERPs provide high temporal resolution of the extent of information processing allowing researchers to access to both sensory and cognitive processes involved in complex decision-making.

Keywords

• Event-related potentials
• data acquisition,
• stimulus parameters
• EEG
• Artifact