This title enables readers to understand how to undertake appropriate neurophysiological investigations in the critical care setting. The book addresses the scientific principles (biological and technological), recording techniques, the development of electrical potentials in normal subjects, and the ways these are disturbed by trauma, surgery and disease. The impact of digital technologies and the possibilities of quantification, statistical treatment and advanced signal processing techniques have enabled practitioners to work to more rigorous scientific standards. The increasing availability of such tools in daily clinical work means that patients can now benefit from investigations of known specificity and sensitivity.