In the depths of Straub Hall, researchers in the Brain Electrophysiology Lab (BEL) are using advanced measurements of brain activity to show how mood disorders motivate the brain’s interpretation of daily events.
It would make sense that a depressed person could see things in a negative way. But through the measurement of electrical waves emitted by the brain, researchers for BEL have determined that moods have a direct effect on other cognitive processes in the brain, such as attention span and memory.
“We’re looking at different brain functionality as a function of depression,” said Lynn McDougal, research assistant and lab coordinator for BEL. “How people operate on an emotional level, signaled by things in their environment.”
Through measurements of event-related brain potential, or ERP, researchers report they have observed that “clinically significant states of depression and anxiety may be associated with negative biases in cognition and judgment.”
This is just one study BEL’s team of 15 researchers — made up of post-doctorate students, graduate students and visiting professors — are pursuing at the laboratory. These researchers are examining everything from language to the brain’s perception of time and music.
Using a Geodesic Sensor Net, data-collection and data-acquisition systems to measure brain activity of students and others who volunteer for laboratory experiments, researchers are combining the techniques of cognitive psychology and brain studies to gain a better understanding of how the brain works.
This “neural net” uses a dense array of sensors that cover a person’s scalp and face to measure electric current flow emitted by the brain, McDougal said.
“We don’t need to cut open a person’s head and poke them with electrodes to gain information on what’s going on,” McDougal said.
Though this analysis is only skin deep, researchers said there are other ways to get inside the brain.
“We observe the neural activity that could be generating the effects we see in the scalp and on the surface,” said Gwen Frishkoff, a doctoral student and researcher for BEL.
Once the “neural net” is in place, the researchers employ a combination of stimuli to arouse emotional reactions in the brain.
In a study graduate student Richard Desmond is conducting, researchers are determining how people evaluate themselves and others through the use of language. Volunteers donned the net and were seated before a computer screen and asked to answer “yes” or “no” to words that describe themselves — words common in student jargon, such as “geeky,” “happy,” “outgoing,” “mad” or “sad.”
After describing a person they know, volunteers are then asked to see if any of those same words apply to themselves. This shows if there is a “difference in the way we evaluate other people as compared to ourselves,” Desmond said.
“What we found is that there is not much difference,” he continued. “The reason may be that a lot of people are identifying a close friend with themselves. We’ll have to design a different experiment to test that.”
But Desmond said some interesting ideas have been gleaned through this research.
One is the “valence effect,” the difference in the brain’s reaction to words that invoke something positive, rather than evoking a negative association, he said.
“There is a big difference in brain activity which correlates with asking something that is seen as good or bad,” he said.
Another interesting find revolved around the brain’s different activity when answering “yes” or “no.” Desmond calls this the “endorsement effect.”
“Something different occurs in the brain when you’re planning to say yes,” he said.