Are you able to start a task and stick to it to the end, ignoring the temptations of the internet or the sudden realization that you should probably do laundry?
Or maybe you should be doing something else right now?
The power that allows people to make plans or goals, and achieve them without losing focus, is called cognitive control. Healthy individuals vary widely in their ability to use cognitive control, and many neuropsychiatric disorders have been linked to problems with cognitive control.
But there’s a lot researchers still don’t know: exactly how and why cognitive control varies from person to person? What areas of the brain are affected? What is the connection between brain activity and behavior?
Todd Braver, professor of psychology and brain sciences in Arts & Sciences, as well as radiology and neuroscience appointments at Washington University School of Medicine in St. Louis, works to answer these questions . He and his research team believe they have developed a more robust research method, and they recently published the first of what promises to be numerous studies examining the brain’s basis of cognitive control both in individuals and between groups. .
Their first findings were published online August 19 for the September issue of Journal of Cognitive Neuroscience.
When it comes to researching cognitive control, a typical study is looking at how subjects tackle one or two lab tasks. The results are then generalized to apply to the larger question of interest to researchers.
âWe all know this is not the most valid approach,â Braver said. This is because the cognitive control required to perform a task under one circumstance may not be indicative of different types of tasks under different circumstances. “But due to its simplicity, this is how the field typically approaches these types of research questions.”
To try to get more generalizable results, Braver designed a research framework that not only uses a full battery of cognitive tests, but also examines them under a variety of conditions.
âWe look at a set of tasks and then also try to see how each person behaves when encouraged to use different modes of control,â he said. Each person performed four tasks under three different conditions while being monitored by a functioning MRI. Functional MRI measures changes in blood flow throughout the brain to identify the areas most affected by the tests.
Braver found that the differences in cognitive control appeared to be differences of degree -; common patterns were found in both the brain and behavior of most of the 80 subjects.
“We found consistency between the four tasks in these regions of the brain,” Braver said, “but people varied in degree.” More importantly, and as expected, the changes in brain activity were reflected in changes in task performance levels: participants varied in how they engaged their cognitive control. Together, these results suggest to the research team that the results are more generalizable.
“That’s what matters to us,” he said, “because we believe that effective use of cognitive control should lead to improved performance more generally.”
The four tests are standards of psychology: a task of Stroop; an AX-CPT task; a Cued-TS paradigm; and a Sternberg task.
The four tasks were performed under three conditions. The basic condition was akin to a pop quiz; participants did not know when cognitive control demands would occur. There was a proactive condition, in which participants knew in advance that their cognitive control would be necessary for the task and could prepare accordingly.
Finally, in the reactive condition, the participants did not know the control requirements in advance, but were quickly informed of certain types of tests by the characteristics present.
âIt’s like when you see a stop sign,â Braver said. You don’t know until you see it that you need to stop, but as soon as you spot the color red or the octagonal shape, you start to slow down.
Imaging showed that participants’ brains were in distinct states under each of the three conditions, indicating that there is a qualitative difference when it comes to engaging cognitive control in different situations.
Those who handled tasks better, under all conditions, also showed the most consistent signature of brain activity. But no matter how well people perform, brain states have clustered around similar activity patterns.
This research is the start of what Braver hopes will be a solid understanding, first, of how a healthy brain works.
I don’t think it makes sense to start studying clinical populations without first understanding how cognitive control works in healthy brains. We know that cognitive control shows some of the greatest variation even among healthy people, so we wanted to develop a basic level of understanding in healthy young adults before we branched out. “
Todd Braver, Professor of Psychological and Brain Sciences
Nonetheless, Braver and his research team have high ambitions for this work, with some of the data already made public, so that researchers working in related fields can start using it. Additional studies planned will expand the goal of understanding the genetic basis of cognitive control in identical twins; whether mindfulness training can improve cognitive control function; and the relationship between anxiety and cognitive control.
“We believe that our work and our data are already providing a valuable resource to the scientific community,” said Braver. “And we hope that our team and others can build on this foundation, to better understand why cognitive control is so important, but also so variable, among people.”