Northern Illinois University
Human Auditory Physiology Lab (HAPL)
Allied Health and Communicative Disorders

What is an Event-Related Potential (ERP) and how is it measured?

An ERP is a technique that can be used to assess how the brain is functioning in response to stimulation of the senses (e.g. sight, sound, touch, etc.). It gives a rough idea of how the brain is performing when it comes to abilities related to attention, memory, and information processing.

There are several different ways that ERPs can be measured, but the most common method is to use electrodes that are attached to the scalp. Specific to the HAPL, we use an electrode net like the one pictured to the right. The net consists of soft sponges that are connected together by a series of flexible wires. The structure is very similar to the net that a food service personnel might wear when serving food in a cafeteria. Inside the sponges are electrodes which are designed to pick up brain waves and record them to a computer while an individual performs certain tasks. The brain waves are then analyzed.