The university joined with the Central Texas Veterans Health Care System to procure the scanner and establish the Imaging Research Center. The federal Office of National Drug Control Policy (ONDCP) in the White House provided about $4.6 million for the scanner. The ONDCP is interested in using MRI scanners to study the origins and impact of drug addiction. The university’s Office of the Vice President for Research and its research unit, the Institute for Advanced Technology, spearheaded the university’s efforts in obtaining funding and opening the center. The scanner allows scientists to non-invasively observe activity in the brain. “Major advances in science often occur from equipment and our ability to see things we couldn’t see before,” said Dr. Michael Domjan, director of the IRC and professor of psychology. “The IRC will also allow us to see things we couldn’t see before. In this case it will involve neural structures and neural functions.” The scanner uses radio waves and a strong magnetic field to provide clear and detailed images of tissue and organs. Functional magnetic resonance imaging identifies regions of the brain where blood vessels are expanding, chemical changes are taking place or extra oxygen is being delivered, signs that that part of the brain is processing information and giving command to the body. Huk plans to use the scanner in his research on decision-making. “How neural signals give rise to our abilities to take in sensory evidence, to remember it, to accumulate multiple pieces of evidence and to come up with a chosen course of action,” he said.
His lab’s experiments rely on the measurement of behavior and brain activity. “You can see then that having a functional MRI scanner available is a key element in our research program because it allows us to use human subjects and measure the brain activity while they’re performing tasks,” he said. Subjects in Huk’s studies respond to a visual stimulus such as a pattern on a screen. They make a decision about what it looks like and report it by pressing a button. Questions could be, “Was there motion on the screen that moved primarily to the left or right? Was this more red than green? Or was it brighter or darker than the one you saw before?” “Those simple kinds of perception decisions are kind of our first step of understanding simple forms of cognitive function at the neural level,” Huk said. He said those simple experiments are good because there is a wealth of more detailed studies in non-human primates that use the same approach. Much of that research suggests that many of the simple sensory and motor areas of the brain involved in performing such tasks are similar in humans and certain kinds of macaque monkeys. “That’s another advantage,” Huk said. “It allows us to make inferences about human behavior, magnetic resonance imaging studies, monkey behavior and electrophysiological recordings of neural activity in the monkeys as they perform these tasks.” Dr. Swathi Kiran, an assistant professor in the Department of Communication Disorders, uses a scanner at UT Southwestern Medical Center in Dallas in collaboration with researchers there.
Kiran studies aphasia, an impairment of the ability to communicate that affects 25 percent of stroke victims. She develops therapy that helps patients regain that ability, to some degree. “They all show improvements after we provide them therapy,” she said. “We’re now looking at changes in specific regions in the brain as a result of this therapy we’re providing.” That’s where the scanner comes in. She plans to use it to look at the subjects’ brain function before therapy and after therapy to see what neurological changes occur because of therapy. Getting images of those changes as a result of therapy in aphasic patients is an emerging area of research. She said the work offers the best chance of really improving the therapies available to aphasic patients. “Ultimately, my aim is to find out how the brain is capable of change,” she said. “I know how therapy works, but maybe there’s a better way of doing this. If I knew how the brain can reorganize itself, I could then go back and see what kind of therapies we could design to get people back to 100 percent.” Kiran also studies how stroke and therapy affect people who speak two languages. “One of the things we can do with the scanner is to look at how language is represented in bi-lingual people,” she said. “We have normal bilingual people performing language tasks in the scanner and then try to look at bilingual stroke patients with language deficits and examine how undamaged areas function in brains that can represent two or more languages. While these studies hone in on specific areas, Huk said the scanner is a tool that offers the opportunity for scientists in different disciplines to work together. “It offers the opportunity of really bringing home the promise of interdisciplinary research,” he said. “Our search committee (for faculty recruiting) has people from computer science, physics, psychology, neuroscience and other related fields. It’s truly collaborative.” Tim
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