, Volume 16, Issue 1, pp 144–165 | Cite as

The Potential for a Speech Brain–Computer Interface Using Chronic Electrocorticography

  • Qinwan RabbaniEmail author
  • Griffin Milsap
  • Nathan E. Crone


A brain–computer interface (BCI) is a technology that uses neural features to restore or augment the capabilities of its user. A BCI for speech would enable communication in real time via neural correlates of attempted or imagined speech. Such a technology would potentially restore communication and improve quality of life for locked-in patients and other patients with severe communication disorders. There have been many recent developments in neural decoders, neural feature extraction, and brain recording modalities facilitating BCI for the control of prosthetics and in automatic speech recognition (ASR). Indeed, ASR and related fields have developed significantly over the past years, and many lend many insights into the requirements, goals, and strategies for speech BCI. Neural speech decoding is a comparatively new field but has shown much promise with recent studies demonstrating semantic, auditory, and articulatory decoding using electrocorticography (ECoG) and other neural recording modalities. Because the neural representations for speech and language are widely distributed over cortical regions spanning the frontal, parietal, and temporal lobes, the mesoscopic scale of population activity captured by ECoG surface electrode arrays may have distinct advantages for speech BCI, in contrast to the advantages of microelectrode arrays for upper-limb BCI. Nevertheless, there remain many challenges for the translation of speech BCIs to clinical populations. This review discusses and outlines the current state-of-the-art for speech BCI and explores what a speech BCI using chronic ECoG might entail.

Key Words

Electrocorticography (ECoG) Brain–computer interface (BCI) Neural speech decoding Automatic speech recognition (ASR) Locked-in syndrome (LIS) Communication 



The authors of this paper have been supported by the National Institutes of Health (R01 NS091139).

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Copyright information

© The American Society for Experimental NeuroTherapeutics, Inc. 2019

Authors and Affiliations

  • Qinwan Rabbani
    • 1
    Email author
  • Griffin Milsap
    • 2
  • Nathan E. Crone
    • 3
  1. 1.Department of Electrical EngineeringThe Johns Hopkins University Whiting School of EngineeringBaltimoreUSA
  2. 2.Department of Biomedical EngineeringThe Johns Hopkins University School of MedicineBaltimoreUSA
  3. 3.Department of NeurologyThe Johns Hopkins University School of MedicineBaltimoreUSA

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