ADVANCED REVIEW
The time-course of speech perception revealed by
temporally-sensitive neural measures
Laura M. Getz
1
| Joseph C. Toscano
2
1
Department of Psychological Sciences,
University of San Diego, San Diego,
California
2
Department of Psychological and Brain
Sciences, Villanova University, Villanova,
Pennsylvania
Correspondence
Laura M. Getz, Department of
Psychological Sciences, University of San
Diego, 5998 Alcala Park, San Diego, CA
92110, USA.
Email: lgetz@sandiego.edu
Abstract
Recent advances in cognitive neuroscience have provided a detailed picture of
the early time-course of speech perception. In this review, we highlight this
work, placing it within the broader context of research on the neurobiology of
speech processing, and discuss how these data point us toward new models of
speech perception and spoken language comprehension. We focus, in particu-
lar, on temporally-sensitive measures that allow us to directly measure early
perceptual processes. Overall, the data provide support for two key principles:
(a) speech perception is based on gradient representations of speech sounds
and (b) speech perception is interactive and receives input from higher-level
linguistic context at the earliest stages of cortical processing. Implications for
models of speech processing and the neurobiology of language more broadly
are discussed.
This article is categorized under:
Psychology > Language
Psychology > Perception and Psychophysics
Neuroscience > Cognition
KEYWORDS
acoustic cue encoding, gradiency, speech perception, top-down effects
1 | INTRODUCTION
Questions about spoken language have a long history in neuroscience research. Indeed, the uniqueness of language to
humans and the resulting lack of animal models means that neurobiological investigations have been fundamental to
our understanding of language comprehension. Moreover, recent advances in cognitive neuroscience techniques have
provided an increasingly detailed picture of the early time-course of speech perception. This review will highlight that
work, placing it within the broader context of research on the neurobiology of spoken language processing and dis-
cussing how these data can point us toward new models.
Research investigating the neural basis of language can be broadly divided into studies addressing questions about
where in the brain different stages of language processing occur (primarily using fMRI methods) and studies investigat-
ing when listeners have access to different types of information in the speech signal (primarily using EEG methods).
Early work by Penfield and Roberts (1959) with surgical patients helped to identify brain areas involved in speech pro-
duction and perception. These studies confirmed the broad involvement of Broca's and Wernicke's areas in production
and comprehension, and the results supported earlier (and subsequent) work with aphasic patients who had damage to
specific cortical areas. This early research informed the development of more recent electrocorticography (ECoG)
Received: 30 November 2019 Revised: 28 May 2020 Accepted: 26 June 2020
DOI: 10.1002/wcs.1541
WIREs Cogn Sci. 2020;e1541. wires.wiley.com/cogsci © 2020 Wiley Periodicals LLC. 1 of 18
https://doi.org/10.1002/wcs.1541