Researchers use neuroimaging to measure early cognitive improvement after mild TBI

Researchers published results of a novel study of the functional activation patterns of working memory after mild traumatic brain injury (TBI). This study, the first to enroll subjects during their initial evaluation in the emergency room, provides new information on the acute effects of TBI on cognition. The fMRI studies, conducted at <72 hours after injury and at one week after TBI, provide neuroimaging evidence for working memory deficits during the week following injury.

The article, Cognitive improvement after mild traumatic brain injury measured with functional neuroimaging during the acute period, was published by PLOS ONE. The authors are Glenn Wylie of Kessler Foundation and the War-related Illness and Injury Study Center of the Dept. of Veterans Affairs, East Orange VA Hospital, and Kalev Freeman, Alex Thomas, Marina Shpaner, Michael O'Keefe, Richard Watts, and Magdalena Taylor of the University of Vermont.

Forty-six participants were enrolled; 27 with isolated mild TBI and 19 controls who had nonsurgical extremity injuries and no head trauma. All underwent fMRI and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). At one week followup, 64% of the TBI subjects reported moderate to complete recovery. Cognitive improvement corresponded with normalization of activation patterns on fMRI.

"We were interested in the effect of concussion on working memory immediately following injury and after one week of recovery," explained Glenn Wylie, DPhil, associate director of the Rocco Ortenzio Neuroimaging Center at Kessler Foundation. "We found increased activation in TBI subjects compared with controls," noted Dr. Wylie. "Also, activation increased as workload increased in the TBI group, and increases were greater in those whose cognition failed to improve. This study is the first step toward understanding the early effects of mild TBI on cognition. Predicting recovery will require the development of effective, low-cost measures that correlate with changes in patterns of brain activation."