Chapter 1
Basics of EEG: Generation, Acquisition,
and Applications of EEG
Chang-Hwan Im
Abstract The purpose of this chapter is to provide comprehensive knowledge about
the generation and acquisition of electroencephalograms (EEGs), which is essential
for understanding the following chapters. The physiological background on the generation of EEGs is presented, and then, a detailed description of the acquisition of
EEG signals is given. Practical applications of computational EEG analysis are also
introduced. Finally, the major advantages and limitations of current EEG technologies are discussed.
1.1 Generation of EEG
An electroencephalogram (EEG) is the flow of neuronal ionic currents recorded
using a pair of electrodes either inside or outside the scalp. The EEG signal recorded
inside the skull, referred to as the intracranial EEG (iEEG), can be used for surgical
planning of intractable epilepsies [15]; however, this is not dealt with in this book
(except in Chap. 8). Throughout this book, “EEG” refers to a scalp EEG recorded
noninvasively from a pair of electrodes attached to the scalp surface.
In comparison with brain metabolism- or hemodynamics-based neuroimaging
modalities, such as positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and functional near-infrared spectroscopy (fNIRS), EEGs can
offer excellent temporal resolution, allowing studies of neuronal dynamics occurring
within a few milliseconds. However, the spatial resolution of an EEG is not comparable to that of an fMRI, owing to the small numbers of spatial data samplings, inherent
volume conduction effect, and physiological and environmental noises/artifacts.
A first human EEG was recorded in 1924 by a German psychiatrist, Hans Berger.
Despite the rapid technological developments, the basic methods for recording EEGs
remain unchanged from Hans Berger’s era. An EEG measures electric potential differences between pairs of electrodes. The electrodes may be either directly attached
C.-H. Im (B)
Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
e-mail: ich@hanyang.ac.kr
© Springer Nature Singapore Pte Ltd. 2018
C.-H. Im (ed.), Computational EEG Analysis, Biological and Medical Physics,
Biomedical Engineering, https://doi.org/10.1007/978-981-13-0908-3_1
3
Basics of EEG: Generation, Acquisition,
and Applications of EEG
Chang-Hwan Im
Abstract The purpose of this chapter is to provide comprehensive knowledge about
the generation and acquisition of electroencephalograms (EEGs), which is essential
for understanding the following chapters. The physiological background on the generation of EEGs is presented, and then, a detailed description of the acquisition of
EEG signals is given. Practical applications of computational EEG analysis are also
introduced. Finally, the major advantages and limitations of current EEG technologies are discussed.
1.1 Generation of EEG
An electroencephalogram (EEG) is the flow of neuronal ionic currents recorded
using a pair of electrodes either inside or outside the scalp. The EEG signal recorded
inside the skull, referred to as the intracranial EEG (iEEG), can be used for surgical
planning of intractable epilepsies [15]; however, this is not dealt with in this book
(except in Chap. 8). Throughout this book, “EEG” refers to a scalp EEG recorded
noninvasively from a pair of electrodes attached to the scalp surface.
In comparison with brain metabolism- or hemodynamics-based neuroimaging
modalities, such as positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and functional near-infrared spectroscopy (fNIRS), EEGs can
offer excellent temporal resolution, allowing studies of neuronal dynamics occurring
within a few milliseconds. However, the spatial resolution of an EEG is not comparable to that of an fMRI, owing to the small numbers of spatial data samplings, inherent
volume conduction effect, and physiological and environmental noises/artifacts.
A first human EEG was recorded in 1924 by a German psychiatrist, Hans Berger.
Despite the rapid technological developments, the basic methods for recording EEGs
remain unchanged from Hans Berger’s era. An EEG measures electric potential differences between pairs of electrodes. The electrodes may be either directly attached
C.-H. Im (B)
Department of Biomedical Engineering, Hanyang University, Seoul, South Korea
e-mail: ich@hanyang.ac.kr
© Springer Nature Singapore Pte Ltd. 2018
C.-H. Im (ed.), Computational EEG Analysis, Biological and Medical Physics,
Biomedical Engineering, https://doi.org/10.1007/978-981-13-0908-3_1
3