Electroencephalogram

The electroencephalogram (EEG) is a widely used non-invasive method for monitoring the brain. It is based upon placing metal electrodes on the scalp which measure the small electrical potentials that arise outside of the head due to neuronal action within the brain. This chapter overviews the fundamental basis of the EEG, the typical signals that are produced, and how they are collected and analysed. Significant attention is given to reviewing the state of the art in EEG collection in both electrode designs and instrumentation hardware. In particular, recent developments in ear EEG and in conformal tattoo electrodes for very long term monitoring are highlighted. The chapter concludes by overviewing the applications of EEG technology in medical and non-medical domains, demonstrating the emergence of ‘consumer neuroscience’ applications as EEG devices become more available and more readily useable by non-specialist operators.