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 2 - Polarity and Montages
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 discusses the concepts of polarity and montages including the implications of polarity, the types of montages, and how to use different montages during analysis. Polarity depends on the relative difference between two potentials with the pointer always deflecting toward the relatively smaller potential. Cerebral potentials thus generate electrographic waveforms on the screen. Montages are specific arrangements of channels (pair of recording electrodes), each allowing appreciation of the waveform from a specific point of view. Bipolar montages consist of channels with adjacent electrode pairs and referential montages consist of channels with nonadjacent pairs. Bipolar montages are less prone to artifact and useful to analyze focal potentials. Referential montages are somewhat more prone to artifact contamination and more useful to analyze broader potentials. In this chapter, readers will learn to use both types of montages for analysis. [137 words/830 characters]
Information
- Type
- Chapter
- Information
- How to Read an EEG , pp. 15 - 23Publisher: Cambridge University PressPrint publication year: 2025
References
Niedermeyer, E. The EEG signal: polarity and field determination. In Electroencephalography: basic principles, clinical applications, and related fields; Niedermeyer, E, Lopes de Silva, FH, Eds. (pp. 79–83). Urban & Schwarzenberg, Baltimore; 1987.Google Scholar
Sinha, SR, Sullivan, LR, Sabau, D et al. American Clinical Neurophysiology Society guideline 1: minimum technical requirements for performing clinical electroencephalography. The Neurodiagnostic Journal. 2016 Oct 1;56(4):235–4.CrossRefGoogle ScholarPubMed
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