Part electrical engineer and part neurophysiologist, Dave Rector often will be found tucked in a far corner of the College of Veterinary Medicine surrounded by a jumble of colored wire, black electrical tape and socket sets. A slight hint of rodent scents the air while a periodic table of the elements hangs above a bubbling lobster tank. Behind his soft-spoken demeanor, Rector’s intensity and vision give his work a futuristic aura — the projects taking place in this unlikely laboratory are quietly breaking down century-old theories in the study of brain function.
As associate professor in the Department of Veterinary and Comparative Anatomy, Pharmacology and Physiology (VCAPP) and the Neuroscience Program, Rector is involved in a number of revolutionary studies. With his help, a world of often unpleasant medical exams may soon give way to diagnostics much easier to bear.
Take scattered-light brain imaging, for example. Studies have shown that when nerve cells are stimulated, changes take place that can be measured by bouncing light off the tissue and measuring its reflectance. It is possible to measure these differences in reflectance for every physiological state. Someday, instead of the usual poking and prodding by a doctor or the claustrophobic MRI experience, you may simply lie down while beams of colored light scan your body. Causing no discomfort, the light “scatters” off various tissues and provides a full diagnosis of all brain and body functions.
“Light can be used as a tool for virtually anything that medicine has tried to accomplish over the past millennium,” says Rector. “High-powered lasers are used to cut tissue during surgery, medium-power laser light can stimulate nerves and other tissues without damage, and by detecting changes in low-power light, we can create images of brain activity in three dimensions. Our ultimate goal is to replace the X-ray, MRI, PET and CT scan with low-power optical scanning techniques, which are both less invasive and less expensive.”
Rector and his team have successfully created surface maps of the rat brain, showing which parts of the brain are doing what. They plan to begin human brain mapping in spring 2007 using a special helmet that contains hundreds of fiber optic connections — or optrodes — that attach to the scalp.
Assisting him in this effort are Jennie Schei, graduate student in physics, and Amanda Foust, senior in neuroscience. Also involved in the design process are Matt McCluskey, associate professor and chair of the Department of Physics, and George La Rue, associate professor, and Deuk Heo, assistant professor, both in the Department of Electrical Engineering.
Their plan is to develop a helmet that can perform both functional and structural brain imaging and diagnosis. Funded by the National Institute of Mental Health, Rector’s team expects to have a functional prototype available to the public within the next two to three years.
Sleeping cortical columns
The helmet also will be used to image the brain continuously during sleep — specifically measuring activity in the cortical columns, which has never been done before. This is not surprising since it was Rector, together with Jim Krueger, professor in VCAPP, who recently discovered that the brain does not sleep all at once; rather, it sleeps in variable shifts of related brain cells called cortical columns.
In essence, different parts of the brain can be asleep at different times. Those brain cells that have been required to work the hardest are the first to enter the sleep state. When enough cortical columns “fall asleep,” the whole animal/person goes to sleep.
Though it had been previously shown that half of the brain can sleep independently of the other half in marine mammals, Rector’s discovery is groundbreaking in that he has identified the smallest unit of the brain that actually sleeps.
Through use of the optical helmet, Rector and his colleagues — in collaboration with Greg Belenky and Hans VanDongen at the WSU Spokane Sleep and Performance Research Center — hope to detect when different parts of the human brain are tired and from there predict when mistakes are more likely to be made. In the future, people in occupations from truck driver to flight controller may use similar technologies to plan safe and effective work schedules.
The brain as a hologram
To break it down even further, Rector is proposing that the brain no longer be thought of as a circuit with wires, but as a substrate for electromagnetic waves — or a hologram. In a study funded by the Beckman Foundation in 2003, Rector drew from the observations of others to create a new theory of basic brain function. He is proposing that the purpose of the brain is to set up electromagnetic “standing” waves in response to stimulation.
This is something like when two pebbles are thrown into a pond. The ripples — waves — intersect and lead to sensory perception.
“As holograms change their appearance when looked at from different angles,” said Rector, “so would the electromagnetic waves in the brain create different perceptions with each experience.”
This theory is evident in the 3-D videos his lab has recorded of standing waves in rat brains. The size and amplitude of the wave varies in response to precise stimuli, such as individual whiskers being twitched.
Practically speaking, this idea may revolutionize the way medicine deals with brain disease.
“The theory of the brain operating as an electrical circuit does not always explain the results of brain injury or disease. In many cases, there is damage to a specific area of the brain, but people recover and do just fine,” Rector said.
“Looking at the brain as a hologram may allow doctors to become much more effective in treating disease — potentially developing stimulation protocols to match an individual’s brain waves and thereby creating prosthetics for any neurological function in the body.”
Family, church, community
Research is demanding, and those who do it may struggle to balance time between work and the rest of life. It’s no different for Dave Rector, who spends countless hours in his laboratory each week. Yet with the support of his wife and love of his two young children, he has managed to place family and community high on his list of priorities.
An active leader in Pullman’s Emmanuel Baptist Church, his faith motivates his vocation.
“One of the reasons I was interested in becoming a scientist was to learn more about God’s creation — and my position in the university helps me to remain open-minded.”
Community activities:
• President, Montessori school board
• Leads 4th-grade AWANA (Bible/activities) class, Emmanuel Baptist Church
• Leads small-group Bible study/fellowship, Emmanuel Baptist Church
Craftsmanship
What do you do when your research ideas outrun the current technology? In Dave Rector’s case, he walks across the hall to his machine shop and builds that circuit board or miniature implantable video camera.
“We can’t fabricate microcircuits,” he concedes. “We have to send out for those. But for everything else, if we can buy the components, we can build it.”
As if for inspiration, the first computer he built at age 10 hangs on the wall above his desk. Scattered below it are mounds of handcrafted devices ranging from simple brackets to the most intricate electronics.
Among them is a tiny photodiode used for making optical measurements — much like a camera. The device is implanted in freely moving rats to measure photon (the basic unit of light) production at sunrise each morning. It is then that a certain
gene — similar to one found in fireflies and coupled to the rat’s circadian rhythm gene — activates and causes every living cell in the animal to glow fluorescent green.
By measuring the emitted photons, Rector and colleague Heiko Jansen, assistant professor in VCAPP, hope to better understand how daily physiological cycles affect sleep and lead to problems such as jet lag.
In another project, funded by the National Institute of Mental Health, Rector — together with electrical engineers George La Rue and Deuk Hoe — has developed a tiny 16-channel physiological amplifier on a chip.
“This amplifier currently outperforms any existing amplifier in the world,” said Rector, “and it has a built-in computer system, with a high-speed wireless transmitter, for converting electrical and optical signals into digital data.” It is this amplifier that will be connected to hundreds of similar chips for use in the optical imaging helmet the team has developed for scanning human brain function.
“We call this our neurophysiological diagnostic laboratory in a helmet,” Rector said. “With it, we should be able to handle and process any type of physiological information such as EEGs and scattered-light readings.”
Commitment to education
For researchers intent on winning grants and publishing papers, teaching sometimes takes a back seat. But according to Bryan Slinker, professor and chair of VCAPP and director of neuroscience, Dave Rector specifically chose to come to WSU for the value the institution places on undergraduate and graduate education.
“Dave is also highly committed to K-12 outreach,” he said. “For example, he has long overseen the Neuroscience Program KidsJudge!, an event for fifth graders during Brain Awareness Week.”
Rector recently submitted a grant to the Howard Hughes Medical Institute to fund a “Role Models for Science” program, in which researchers would mentor K-12 students with their science-fair projects. And he hopes to participate in the Pipeline Program, a statewide WSU outreach to interest and graduate more students in science and math. It is being submitted to the Washington Legislature by WSU in the 2007 session.
