Book contents
- How to Read an EEG
- Reviews
- How to Read an EEG
- Copyright page
- Dedication
- Contents
- Figure Contributions
- Foreword to the First Edition
- Preface
- How to Read This Book
- Part IBasics
- Chapter 1Introduction
- Chapter 2Polarity and Montages
- Chapter 3Localization
- Chapter 4Frequency and Rhythm
- Chapter 5Maturation
- Chapter 6Normal Adult EEG
- Part IIInterpretation
- Part IIISpecific Conditions
- Appendix:How to Write a Report
- Index
- References
Chapter 6 - Normal Adult EEG
from Part I - Basics
Published online by Cambridge University Press: 27 September 2025
Book contents
- How to Read an EEG
- Reviews
- How to Read an EEG
- Copyright page
- Dedication
- Contents
- Figure Contributions
- Foreword to the First Edition
- Preface
- How to Read This Book
- Part IBasics
- Chapter 1Introduction
- Chapter 2Polarity and Montages
- Chapter 3Localization
- Chapter 4Frequency and Rhythm
- Chapter 5Maturation
- Chapter 6Normal Adult EEG
- Part IIInterpretation
- Part IIISpecific Conditions
- Appendix:How to Write a Report
- Index
- References
Summary
This chapter focuses on recognizing the features of a normal adult EEG during wakefulness, drowsiness, and various stages of sleep. The EEG normally remains consistent during adult life and should be interpreted in the context of physiological state. Normal wakefulness is characterized by a reactive posterior dominant alpha rhythm, anterior faster beta activity, eye blinks, and muscle artifact. Drowsiness is characterized by attenuation of the posterior dominant rhythm, diffuse slowing into theta range, emergence of slow lateral eye movements, and dissipation of muscle artifact. Vertex waves and positive occipital sharp transients of sleep (POSTS) occur during stage N1 sleep, and stage N2 sleep is characterized by K complexes and sleep spindles. Diffuse high amplitude semirhythmic delta slowing is present in stage N3 sleep and saw tooth waves occur in rapid eye movement (REM) sleep. [134 words/763 characters]
Information
- Type
- Chapter
- Information
- How to Read an EEG , pp. 57 - 68Publisher: Cambridge University PressPrint publication year: 2025
References
Tatum, WO IV, Husain, AM, Benbadis, SR, Kaplan, PW. Normal adult EEG and patterns of uncertain significance. Journal of Clinical Neurophysiology. 2006 Jun 1;23(3):194–207.CrossRefGoogle ScholarPubMed
Villamar, MF, Gilliam, FG. Dyshormia in focal epilepsy. Arquivos de neuro-psiquiatria. 2018 Jul;76(7):495–6.10.1590/0004-282x20180045CrossRefGoogle ScholarPubMed
Eisermann, M, Kaminska, A, Moutard, ML, Soufflet, C, Plouin, P. Normal EEG in childhood: from neonates to adolescents. Neurophysiologie clinique/Clinical Neurophysiology. 2013 Jan 1;43(1):35–65.CrossRefGoogle ScholarPubMed
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