Washington, April 19: A recent research has found that racing neutrons in our brain control and produce thought and action.

Vanderbilt University psychologists Leanne Boucher, Thomas Palmeri, Gordon Logan and Schall applied the children’s game “red light green light,” to their own race model of the brain.

“The research provides new insights into how the brain controls movements, which helps explain the impulsivity of people with attention deficit and hyperactivity disorder,” study co-author Jeffrey Schall, E. Bronson Professor of Neuroscience at Vanderbilt University, said. “It also shows how mathematical models can be used to discover how the brain produces thought and action.”

The new paper uses physiological data collected in Schall’s laboratory to demonstrate how a theoretical model Logan developed more than 20 years ago is executed by the brain.

“I developed the race model to explain behavior on a task called the stop signal task with a friend of mine, William Cowan, who is a theoretical physicist, in the 1980s,” Logan, Centennial Professor of Psychology, said.

Stop signal tasks gauge an individual’s ability to discontinue a premeditated action, like pressing a key on a keyboard or looking at a target, in response to a signal.

“Our race model proposed that two independent processes were underway, one telling us to ‘go’ and one telling us to ‘stop’ in response to the stop signal. Applying the model to children’s behavior revealed that stop signal task times are significantly longer in children with attention deficit and hyperactivity disorders than in other children,” he said.

The model has been broadly acknowledged and has also been used to elucidate cognitive problems in people with obsessive-compulsive disorder, schizophrenia and Parkinson’s disease.

“We think of people who are impulsive as acting too quickly,” Logan said. “Kids with ADHD are actually slower on the ‘go’ task than the control kids. It’s not that they go too quickly; they stop too slowly.”

“The model proposes that there are two processes happening in our brain, one making us ‘go’ and another making us ‘stop,’” Boucher, a postdoctoral fellow, said. “However, as neurophysiologists, we know these processes are intricately linked, not independent. Our goal with this paper was to resolve that paradox.”

To answer this question, the researchers monitored brain activity in monkeys while they were performing a visual stop signal task. In those experiments, the monkeys were taught to look at a visual target unless a stop signal came on, in which case they were supposed to refrain from looking at the target.

“We knew that the neurons responsible for the ‘go’ and ‘stop’ actions were located in the parts of the brain that control movements,” Boucher said. “Each trial began with the illumination of a target in the periphery that the subject was supposed to look at. This is when the ‘go’ unit was activated. Sometimes a ‘stop’ signal came on and the subject had to inhibit their eye movement. This is when the ‘stop’ unit was activated.”

The researchers found that the results forecasted by the model and those shown by the neural activity matched.

The findings are some of the first to link cognitive research and neurophysiology—making the connection between the mind and the brain.

“For years, one group of researchers was looking at what neurons are doing, and a different group of researchers was looking at what people are doing,” Palmeri, associate professor of psychology, said. “Now there is a point of contact between decades of important research in neurophysiology and decades of important research in cognitive modeling. Research that has very different histories and approaches is really starting to come together.”

“You develop a model to explain behavior and in many ways it’s just made up,” Logan said. “But then you find out that it says something about what the neurons are doing, and that’s exciting.” (ANI)