Maybe the ERP components to the picture and the word are biggest at the same time, but they are biggest over different parts of the head. For example, let’s say we want to know if different parts of the brain are used when you see a picture of an apple, and when you read the word “apple”. This doesn’t really tell us where in the brain the signals are coming from, but it can be useful in telling us whether two ERP components come from the same place or not. By putting lots of electrodes all over the scalp (in our lab we use 64 or 128 electrodes), we can get some idea of where the ERP components are strongest. One of the big disadvantages of EEG/ERP is that it’s hard to figure out where in the brain the electrical activity is coming from. One of the biggest advantages to EEG/ERP is the ability to see brain activity as it unfolds in real time, at the level of milliseconds (thousandths of a second). By looking at the timing of these blips (technically called “components”) we can gain a better understanding of how different types of information are processed, and when. Within the first second of seeing a stimulus, like a word or a picture, the brain generates a series of “blips” in the ERP brain wave that indicate the activity of different brain systems that are involved in perceiving and making sense of that stimulus. This is a specific use of EEG in which we look at brain waves that are generated in response to particular events, such as seeing a word or picture on a computer screen. The basic way that information is processed by the brain is by very complex connections (networks) of neurons communicating with each other using electricity.ĮRP stands for “event-related potentials”. Measuring electrical activity from the brain is useful because the brain uses electrical impulses to operate – electrical signals travel along brain cells (neurons).

EEG does this using electrodes that are placed on the scalp.

This is a technique for recording “brain waves”, or more technically the electrical activity produced by the brain.

Brain eeg