The human brain is utterly bombarded with stimuli each moment of the day, yet people are remarkably able to carry on conversations in crowded rooms and read textbooks while simultaneously listening to the music from the dorm room down the hall. Although this multitasking might seem like a mundane, everyday activity to the average person, the power of concentration and the ability to pay attention to specific stimuli requires remarkable brain power.
In an attempt to better understand the process of awareness in humans, a group of researchers from Tufts and Boston University worked collaboratively to create a computational model linking gamma oscillations in the brain to attention. These oscillations, also known as gamma waves, have been linked to concentration and the ability of the brain to control its sensory input.
Tufts Professor of Mathematics Christoph Börgers, one of the project's researchers, explained that the goal of the study was to further scientists' understanding of the physical processes that occur in the brain when people and animals adjust their attention to grasp one thing while filtering out another.
Börgers hopes that his work will someday aid in the treatment of attention disorders, and that by better understanding attention, other researchers will be able to make continued progress in the field.
"The hope in all this work is that it will inform people in medicine," he said.
According to Börgers, concentration consists of two parts. First, the brain must identify which stimuli are important, and second, it must filter out irrelevant information.
In an attempt to examine when each of these parts occurred, the researchers used an electroencephalograph (EEG), which detects brain waves. Pulses of electrical energy from the brain create electrical wave patterns, which are read on the EEG, and depending on the type of task one is performing, one's state of mind or whether one is asleep, different wave patterns will be detected.
Börgers, along with his colleagues Nancy Kopell and Steven Epstein of Boston University's Department of Mathematics and Center for Biodynamics, modeled how excitatory and inhibitory neurons work in the brain.
The simulation showed that when excitatory neurons become overstimulated, gamma oscillations cannot be achieved, and additional information cannot
be processed.
The researchers hope that this model will effectively illustrate how and why a person has difficulty thinking or sorting out input from their senses when too much is going on around them. This may explain why it is so hard to study in a noisy environment or in front of the television.
Börgers became interested in biological mathematics as an extension of his area of study. When a colleague asked him to accompany her to seminars at Boston University covering computational biology, he became excited about the field.
As a computational biologist, he takes mathematical concepts and applies them to scientific endeavors. Although mathematicians do not typically have a reputation for involving themselves heavily in medical research, Börgers emphasized that mathematics can play a useful role in medicine, as has been the case with Parkinson's disease in the past few years.
"Mathematicians are trying to make computational models to understand what is going on ... during deep brain stimulation on patients," he said. "It is conceivable that you could [research medicine] more efficiently if you [understood] the mechanisms in a more fundamental way."
His design, however, does not apply all of the detail that the human nervous system possesses.
"In this type of modeling, we do not aim at reproducing biological complexity in detail," he said.
By creating a simpler model, computational biologists are able to remove many of the complexities that plague conventional scientific experiments. After getting to the essence of the question of study, more intricate models can be built.
Amid his current success, Börgers has confidence that further research will continue in the same direction.
