Cortical activity underlying overt and covert language generation measured using high-density diffuse optical tomography

Mariel L. Schroeder; Andrew K. Fishell; Arefeh Sherafati; Alexa M. Svoboda; Joseph P. Culver; Adam T. Eggebrecht

doi:10.1117/12.2526854

11 July 2019 Cortical activity underlying overt and covert language generation measured using high-density diffuse optical tomography

Mariel L. Schroeder, Andrew K. Fishell, Arefeh Sherafati, Alexa M. Svoboda, Joseph P. Culver, Adam T. Eggebrecht

Author Affiliations +

Proceedings Volume 11074, Diffuse Optical Spectroscopy and Imaging VII; 110740H (2019) https://doi.org/10.1117/12.2526854
Event: European Conferences on Biomedical Optics, 2019, Munich, Germany

Abstract

Using naturalistic language generation tasks (e.g. overt speech) to capture the neural correlates of speech production is important, as less naturalistic (but often used) tasks such as covert language generation are not a reliable substitute for accurately assessing cortical activation associated with naturalistic speech. fMRI poses challenges to implementing naturalistic language tasks, especially in clinical populations, because it is noisy, physically constraining, and contraindicated in populations with metal implants. High-density diffuse optical tomography (HD-DOT) is particularly well-suited for naturalistic language tasks because it is silent, wearable, portable, and metal-compatible. This study investigates cortical activity underlying naturalistic language generation using HD-DOT. Six adult subjects aged 20-26 years completed two scans on two separate days consisting of three different tasks: covert word reading (RW), covert verb generation (CV), and overt verb generation (OV). Cortical responses were apparent in expected anatomical areas for all tasks and RW, CV, and OV evoked responses of increasing strength (peak ΔHbO (μMol) = 7.58, 10.3, and 11.0, respectively). Notably, OV recruits additional activation in Broca’s area and right-lateralized primary motor cortex as compared to CV. These findings are consistent with those obtained using fMRI^9,10,11 and underscore the need to use naturalistic language tasks when assessing the neural representations of natural speech. These results motivate extension to further investigations of naturalistic language processing of increased complexity, both receptive and productive, such as within-room conversation.

Citation Download Citation

Mariel L. Schroeder, Andrew K. Fishell, Arefeh Sherafati, Alexa M. Svoboda, Joseph P. Culver, and Adam T. Eggebrecht "Cortical activity underlying overt and covert language generation measured using high-density diffuse optical tomography", Proc. SPIE 11074, Diffuse Optical Spectroscopy and Imaging VII, 110740H (11 July 2019); https://doi.org/10.1117/12.2526854

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available