Premium
Working memory testing reveals neuroplasticity acutely and longitudinally after mild traumatic brain injury (mTBI)
Author(s) -
Arakaki Xianghong,
Lee Ryan,
Fonteh Alfred N.,
Goldweber Robert T.,
Harrington Michael G.
Publication year - 2018
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.2018.32.1_supplement.878.5
Subject(s) - traumatic brain injury , concussion , neuroplasticity , electroencephalography , medicine , working memory , head injury , cognition , psychology , audiology , poison control , injury prevention , psychiatry , emergency medicine
Background and Objectives There are increasing concerns about mild traumatic brain injury (mTBI) because of its effects in later life. However, objective markers that help physicians quantify the injury are still understudied. We aim to investigate the underlying neuroplasticity reflected by working memory processing after mTBI. Methods We used cognitive brain challenges to explore neuroplasticity in acute mTBI. Brain activities during the N□back working memory (WM) test was investigated using quantitative electroencephalography (qEEG) in an acute and longitudinal mild traumatic brain injury study. mTBI patients (n=22) and controls (n=9) (trauma patients without head injury), 18–50 years of age, were recruited from the emergency department of Huntington Memorial Hospital in Pasadena, CA. Brain challenges were administered using E‐prime software. Data were collected from 21 recording head sensors at four visits: within 1 week, 14 days, 30 days, and 6–12 months after injury (with some missing visits). Behavioral performance as well as spectral power were analyzed to compare the two groups. Brain WM processing were also evaluated by event‐related potentials (ERPs) P300, and corresponding EEG signal (ir)regularity or “noise” level measured by spectral entropy (SE). High SE means signal is more irregular and “noisier”. Results & Discussion Behavioral performance during 0‐back challenge was similar between the two groups, though mTBI patients had significantly lower accuracy than controls during 2‐back at the first visit. qEEG analysis revealed altered brain activities in mTBI group during 0‐back: alpha and beta power were lower in mTBI patients than controls at the second and third visit. Further, theta power during 2‐back at second visit were significantly higher (P=0.0099 and 0.0018) in controls (0.73+/−0.37 and 0.96+/−0.46) compared to mTBI (0.21+/−0.41 and 0.09+/−0.55) patients at the left and right temporal regions. When comparing regional theta power from first visit to second visit, controls were increased (p<0.005), indicating a learning mechanism, while mTBIs were not changed (p>0.10). SE analysis of the EEG signals during the P300 time window demonstrated more irregular or noisier brain signals in mTBI patients. These changes indicate neuroplasticity acutely and longitudinally after mTBI, consistent with learning impairment and “noisier” brain after mTBI. The spectral power and SE under WM challenge are sensitive measures of neuroplasticity after injury, and could be potential objective mTBI markers to help diagnosis, prognosis, or treatment management. Support or Funding Information This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .