Mild traumatic brain injuries are focus of research project

The Centers for Disease Control reports that every year about 280,000 Americans are hospitalized because of traumatic brain injuries, ranging from soldiers injured in Iraq and Afghanistan to football players to auto accident victims.

Corbetta

For a person with mild traumatic brain injury (MTBI), also known as concussion, the disabling long-term effects can include pain, sleep disruption, memory problems, attention deficits and mood swings. A lingering question about these effects has complicated efforts to develop treatments: given that conventional brain scanning techniques typically fail to reveal any permanent structural brain damage in MTBI patients, how do the injuries cause lasting harm?

“Our ability to develop new treatments has been hampered by the lack of a theory backed by solid evidence that explains where these complications come from,” said Maurizio Corbetta, M.D., the Norman J. Stupp Professor of Neurology.

Corbetta is a co-principal investigator on a new multi-institutional research project working to answer these questions, the Attention Dynamics Consortium in Traumatic Brain Injury. The project is funded by a two-year, $3.2 million grant from the James S. McDonnell Foundation. Cornell University, the Universities of California, San Diego and San Francisco, and the Salk Institute of San Diego will also participate.

“This effort to better diagnose and treat the cognitive deficits resulting from MTBI exemplifies our efforts to benefit society through research and scholarship,” said Susan Fitzpatrick, Ph.D., vice president of the McDonnell Foundation.

The collaborators will use multiple methods for scanning the brain to detect subtle anatomical changes and seek potential connections between those changes and functional and behavioral abnormalities. Standard anatomical brain imaging scans will be integrated with three experimental scanning techniques to study patients with MTBI.

The first experimental technique, magnetic resonance diffusion tensor imaging (DTI), produces detailed measurements of water diffusion through tissue. Researchers can use this detail to look for structural damage too fine to be detected with other scans. The second, functional connectivity MRI, detects functional abnormalities caused by subtle anatomical damage. The third, magnetoencephalograpy, very rapidly measures changes in brain activity by detecting small changes in the magnetic fields produced by the brain.

Principal investigator Jam Ghajar, M.D., Ph.D., a neurosurgeon at Cornell University, has already used DTI to uncover evidence that MTBI may damage white matter, a tissue in the brain that connects different brain regions.

“If you view the brain’s gray matter as its computer chips, then white matter is the networking cables connecting the chips,” said Corbetta, also professor of radiology and of neurobiology. “We think the computer chips are normal, but because of damage to the white matter, they’re not talking to each other in a proper way.”

Based on data they gather, researchers will try to create computer models of the disruptions in communications between brain networks.

“This will help both in terms of seeking a way to definitively test who has MTBI and also in terms of our ability to seek better treatments,” said co-principal investigator Gordon Shulman, Ph.D., research professor of neurology.