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Alpha desynchronization/synchronization during working memory testing is compromised in acute mild traumatic brain injury (mTBI)

Authors: Xianghong Arakaki|||Michael Shoga|||Lianyang Li|||George Zouridakis|||Thao Tran|||Alfred N Fonteh|||Jessica Dawlaty|||Robert Goldweber|||Janice M Pogoda|||Michael G Harrington

Journal: PloS one

Publication Type: Journal Article

Date: 2018

DOI: PMC5812562

ID: 29444081

Affiliations:

Affiliations

    Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.|||Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.|||Biomedical Imaging Lab, University of Houston, Houston, Texas, United States of America.|||Biomedical Imaging Lab, University of Houston, Houston, Texas, United States of America.|||Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.|||Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.|||Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.|||Emergency Department, Huntington Hospital, Pasadena, California, United States of America.|||Columbus Biometrics, LLC, Reno, Nevada, United States of America.|||Neurosciences, Huntington Medical Research Institutes, Pasadena, California, United States of America.

Abstract

Diagnosing and monitoring recovery of patients with mild traumatic brain injury (mTBI) is challenging because of the lack of objective, quantitative measures. Diagnosis is based on description of injuries often not witnessed, subtle neurocognitive symptoms, and neuropsychological testing. Since working memory (WM) is at the center of cognitive functions impaired in mTBI, this study was designed to define objective quantitative electroencephalographic (qEEG) measures of WM processing that may correlate with cognitive changes associated with acute mTBI. First-time mTBI patients and mild peripheral (limb) trauma controls without head injury were recruited from the emergency department. WM was assessed by a continuous performance task (N-back). EEG recordings were obtained during N-back testing on three occasions: within five days, two weeks, and one month after injury. Compared with controls, mTBI patients showed abnormal induced and evoked alpha activity including event-related desynchronization (ERD) and synchronization (ERS). For induced alpha power, TBI patients had excessive frontal ERD on their first and third visit. For evoked alpha, mTBI patients had lower parietal ERD/ERS at the second and third visits. These exploratory qEEG findings offer new and non-invasive candidate measures to characterize the evolution of injury over the first month, with potential to provide much-needed objective measures of brain dysfunction to diagnose and monitor the consequences of mTBI.

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