Advanced evoked potentials

Abstract This chapter builds on the principles of common sensory evoked potentials covered in Chapter 9. It covers motor evoked potentials (MEPs), cognitive event-related potentials (ERPs), motor ERPs, event-related oscillations and other event-related responses, as well as vestibular-visual testing. Summarised protocols and interpretation of common findings are presented for the main transcranial magnetic stimulation (TMS) techniques, covering both single-pulse and paired-pulse paradigms (including short-interval intracortical inhibition (SICI), long-interval intracortical inhibition (LICI), intracortical facilitation as well as short-latency and long-latency afferent inhibition). Comparisons are drawn with triple stimulation technique and transcranial electrical stimulation (TES). Technological challenges, paediatric considerations and report writing are also addressed. Cognitive event-related potentials and their clinical applications are explained (including P50, N100, N170, mismatch negativity, N200, P300 (P3a and P3b), N400, P500 and contingent negative variation). Motor ERPs (including Bereitschaftspotentials, movement-related cortical potentials and post-movement potentials) and vestibular evoked myogenic potentials are also covered. Commonly used reference values are included for the key procedures, with particular focus on central motor conduction time for various muscles, central latencies (including age considerations) and conduction velocities.