EEG and transcranial magnetic stimulation. Changing and recording the dynamic flow of visual perception

Murphy, N; Graziadio, S; Taylor, J-P

doi:10.1002/9781118892794.ch8

EEG and transcranial magnetic stimulation. Changing and recording the dynamic flow of visual perception

Lookup NU author(s): Dr Nik Murphy, Dr Sara Graziadio, Jamie Taylor

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

© 2015 by John Wiley & Sons, Ltd. All rights reserved. This chapter explores the use of different electrophysiological methodologies in turn and discusses how they have shed light on the aetiology of visual hallucinations. It draws upon the electrophysiological study of normal visual processing to generate inferences on the causes of visual hallucinations rather than consider direct studies on these phenomena, given the lack of data presently available. In healthy individuals, Electroencephalography (EEG) has been widely used to model neural activity occurring in the primary visual and visual association cortices and it can provide measures of synchrony, coherence and connectivity across time. Using event-related analysis (e.g. electroretinogram (ERG), and visual-evoked potentials (VEP)) and spectral analysis of rhythmic activity, the visual system has been demarcated into a number of discrete processes, including visual input, sensory gating, low-level/early visual processing, and higher visual processing. Another important electrophysiological technique which has been used to investigate the visual system is transcranial magnetic stimulation (TMS).