© 2007 The Author
Journal Compilation © 2007 Blackwell Publishing Ltd
Language and Linguistics Compass 1/6 (2007): 571–591, 10.1111/j.1749-818x.2007.00037.x
Event-Related Potentials and Language
Processing: A Brief Overview
Edith Kaan
University of Florida
Abstract
Since the publication of the first papers on event-related brain potentials
(ERP) and language in the 1980s, the field of electrophysiology of language
has evolved a great deal. This article is a brief overview of ERPs and language-
processing research. It discusses how ERPs are derived, provides the pros
and cons of using ERPs for language-processing research, and gives a summary
of the major ERP components relevant to research on speech perception
(mismatch negativity), word and sentence comprehension (N400, left anterior
negativity, P600), and word production (lateralized readiness potential, N200).
Additionally, it addresses current controversies concerning the interpretation
of these components. Applications of the ERP technique are illustrated
with research on first and second language acquisition, bilingualism, and
aphasia.
Introduction
Language processing occurs at an extremely fast rate. Words are recog-
nized in well under a half of a second, and the difference between per-
ceiving /d/ vs. /t/ comes down to a difference in voicing onset of a few
milliseconds. To fully understand that stages are involved in language
processing and their timing, psycholinguists need a method that has very
good temporal resolution. Recording event-related brain potentials (ERPs)
is such a technique.
This article discusses the pros and cons of using ERPs in language-
processing research, introduces some of the key language-related ERPs
components and current controversies, and illustrates how ERPs have
been used to address issues in first and second language acquisition and
aphasia. The overview below is not intended to be an exhaustive review.
For more comprehensive overviews of ERP components related to
language processing, see Kutas et al. (2006) and Hagoort et al. (1999); for
more details on the technical and methodological aspects of the ERP
technique, see Luck (2005).

572 Edith Kaan
© 2007 The Author Language and Linguistics Compass 1/6 (2007): 571–591, 10.1111/j.1749-818x.2007.00037.x
Journal Compilation © 2007 Blackwell Publishing Ltd
What Are ERPs?
OBTAINING ERPS
Electrical brain activity can be recorded by placing electrodes on a per-
son’s scalp. ERPs are obtained by presenting the participant with stimuli
and/or a certain task, and recording the electrical potentials (brain waves)
from the start of the stimulus or other event of interest. These potentials
are then averaged over a large number of trials of the same type, yielding
the ERP. Averaging will enhance the brain potentials that are related to
the onset of the event, and will reduce brain potentials that are not tied
to the onset of the event and are assumed to be random. A typical ERP
is displayed in Figure 1. Time in milliseconds is depicted on the x-axis,
with ‘0’ corresponding to the onset time of the relevant stimuli or
events; the y-axis represents voltage differences in microvolts. In this
figure, negative polarity is plotted up. Figure 1 displays the ERP for only
Fig. 1. Illustration of how ERPs are obtained. Electrical activity is recorded from the scalp while
the participant is, for example, reading or listening to words. The signal thus obtained is
amplified and averaged, time-locked to the stimulus of interest, yielding the ERP. Usually, two
or more conditions are compared (represented by the solid and dotted line). The MMN (mis-
match negativity) component is largest at frontal electrodes, the N400 typically is the largest
at central sites, and the P600 is the largest at parietal locations. See the main text for a
discussion of these components. This figure was originally published as Figure 1 in Osterhout
et al. (1997). Copyright Elsevier 1997. Reprinted with permission from the publisher and the
first author.