Evoked and Event-Related Responses

Abstract This chapter introduces task-related activity, known as evoked and event-related responses. These responses can be elicited by any sudden changes, such as brief transient stimuli, long stimuli, or by “steady-state” stimuli presented in quick succession. Different stimulation setups often require different filter settings for obtaining optimum MEG/EEG signals. The typically recorded signals include transient on- and off-responses, sustained responses during long stimuli, and steady-state responses, and each response can comprise multiple deflections. The commonly used nomenclature of the various types of evoked responses is presented. The chapter closes by examining how evoked responses can be modulated by interstimulus interval, stimulus timing, as well as other stimulus-related parameters.