Psychological studies utilize EEG to study the brain processes underlying attention, learning, and memory. Based on massive trial repetition, ERPs are extracted from the continuous stream of EEG data, which allows characterizing brain processes triggered by the events on a very detailed timescale. Psychiatric fields use EEG to evaluate the patients’ cognitive states, determine lesion sites, and classify symptoms. It can also be used to evaluate the effect of medical and psychological treatment (e.g., in cognitive-behavioral therapy).