SCIENCE

The Arlington Innovation Center: Health Research (AiC: Health Research), of Virginia Tech's National Capital Region, has been awarded a $1.5 million cooperative research and development agreement from the U.S. Army for neuroimaging studies of human performance. The agreement also includes an option for approximately $3 million of future work based on availability of funding.

The Virginia Tech project team is led by Seong K. Mun, professor of physics, research fellow, and director of the center; Kenneth H. Wong, research assistant professor of physics; and Alpay Özcan, research assistant professor, all of whom are members of AiC: Health Research team. Collaborators on the project are Linda Larson-Prior, of Washington University in St. Louis and Zang-Hee Cho, director of the Neuroscience Research Institute at Gachon University in South Korea. Dr. Michael P. Brazaitis, former chair of radiology at Walter Reed Army Medical Center, serves as the Army representative for the project.

"Sleep (or lack of sleep) affects our physical and neurological performance," Mun said. "The central scientific effort of this project will be to improve our understanding of how the brainstem and thalamus regulate sleep in humans, and how these systems are affected by stress and sleep restriction."

Mun said this area has received little attention in the past, largely because it lies deep within the brain in a region that is difficult to study. As a result, most of what is known about this region comes from animal models, which have different sleep patterns than humans. A few human studies have been done in this region, but they result in poor spatial resolution that cannot identify detailed brainstem structures.

"With the technological advances made by Cho's institute in Korea, we now have the capacity to image the living human brain in unprecedented detail," Mun said. "The combination of high resolution positron emission tomography (PET) and 7-Tesla magnetic resonance imaging (MRI) enables us to image brain biochemistry in vivo and precisely localize that activity."

Cho's institute is the only facility in the world with combined imaging capability of 7-Tesla MRI and PET, Wong added.

"This project will focus particularly on serotonin systems in the brainstem and thalamus, because they play a key role in sleep cycling, mood, and stress responses," Wong said. "Dr. Larson-Prior is a noted expert on sleep neuroscience; her laboratory at Washington University will complement the PET/MRI studies with electroencephalography (EEG) and functional connectivity MRI (fcMRI)."

A parallel goal for the project is to create a reference database and teaching files for the Army on advanced MRI methods such as diffusion tensor imaging (DTI) and tractography. "There is currently a great need to help physicians understand and use results from diffusion-based MRI techniques," Özcan said. Özcan will participate in establishing an archive of diffusion studies obtained using the 7T MRI system in Korea.