Poster B42, Sunday, March 26, 8:00 – 10:00 am, Pacific Concourse
EEG Reveals Deficits in Cognitive Control Following Brain Injury
James Cavanagh1, James Broadway1, Kevin Wilson1, Rebecca Rieger1, Andrew Mayer2; 1University of New Mexico, 2Mind Research Network
Many of the disabling aspects of mild Traumatic Brain Injury (mTBI) include lingering deficits in cognitive control. It is widely known that mTBI can damage white matter tracts, but it remains unknown how structural brain damage translates into cognitive deficits. This experiment utilized EEG to define the dysfunctional neural operations that contribute to cognitive problems following mTBI. Acute-stage (< 2 weeks) mTBI patients (N = 12) and healthy age-matched controls (N = 14) completed a dot-probe expectancy version of the AX Continuous Performance Task. It was hypothesized that patients would exhibit diminished proactive control and increased reactive control, which are widely considered to reflect sub-optimal strategic decision abilities. While there were no overt behavioral differences between groups in response time or accuracy, EEG markers of control successfully differentiated groups. Patients had significantly lower P3b amplitudes to the cue indicating the need for proactive control (“B”), as well as increased P3a amplitudes to the probe that required maximal reactive control (“aY”). These findings demonstrate how even in the absence of overt performance deficits, EEG signatures of cognitive control can differentiate mTBI patients from healthy controls. These findings motivate the development of a biomarker for identifying which patients will spontaneously recover from their injury and which patients are at risk of lingering deficits in cognitive control.
Topic Area: EXECUTIVE PROCESSES: Monitoring & inhibitory control