Journal of the International Neuropsychological Society

Research Articles

Acute and Subacute Changes in Neural Activation during the Recovery from Sport-Related Concussion

Thomas A. Hammekea1 c1, Michael McCreaa2, Sarah M. Coatsa3, Matthew D. Verbera4, Sally Durgeriana5, Kristin Floraa6, Gary S. Olsena7, Peter D. Leoa5, Thomas A. Gennarellia2 and Stephen M. Raoa8

a1 Clement J. Zablocki VA Medical Center & Department of Psychiatry & Behavioral Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin

a2 Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin

a3 Rehabilitation Institute at St. Mary's Hospital, Enid, Oklahoma

a4 Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina

a5 Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin

a6 Department of Psychology, Franklin College, Franklin, Indiana

a7 Department of Neuropsychology, Marshfield Clinic, Marshfield, Wisconsin

a8 Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, Ohio


To study the natural recovery from sports concussion, 12 concussed high school football athletes and 12 matched uninjured teammates were evaluated with symptom rating scales, tests of postural balance and cognition, and an event-related fMRI study during performance of a load-dependent working memory task at 13 h and 7 weeks following injury. Injured athletes showed the expected postconcussive symptoms and cognitive decline with decreased reaction time (RT) and increased RT variability on a working memory task during the acute period and an apparent full recovery 7 weeks later. Brain activation patterns showed decreased activation of right hemisphere attentional networks in injured athletes relative to controls during the acute period with a reversed pattern of activation (injured > controls) in the same networks at 7 weeks following injury. These changes coincided with a decrease in self-reported postconcussive symptoms and improved cognitive test performance in the injured athletes. Results from this exploratory study suggest that decreased activation of right hemisphere attentional networks mediate the cognitive changes and postconcussion symptoms observed during the acute period following concussion. Conversely, improvement in cognitive functioning and postconcussive symptoms during the subacute period may be mediated by compensatory increases in activation of this same attentional network. (JINS, 2013, 19, 1–10)

(Received December 21 2012)

(Revised May 30 2013)

(Accepted June 03 2013)

(Online publication July 08 2013)


  • fMRI;
  • Brain activation;
  • Mild TBI;
  • Cognitive compensation;
  • Brain injury;
  • Attention networks


c1 Correspondence and reprint requests to: Thomas A. Hammeke, Clement J. Zablocki VA Medical Center, Acute Mental Health—Neuropsychology, Bldg 111, Room 3301, 5000 W. National Avenue, Milwaukee, WI 53295. E-mail: