Cognitive control relies on both the organization and the integration of brain networks.
“Don’t eat that cake.” “No, you don’t need that cigarette.” “You’ve had enough to drink.”
Eventually you succumb to that seductive piece of pastry, to the call of the nicotine-fiend, to the social pressure of ‘just one more beer’.
And then you ask yourself: “Why don’t I have more self-control?”
Self-control, as we all know, can be quite hard. It’s a complicated thing, combining a lot of different aspects of our cognitive processes. One important part of self-control is what’s known as cognitive control. This means the ability to perform behaviour that is both voluntary and goal-oriented. So, to go back to the first temptation, cognitive control means being able to choose (the voluntary part) not to eat the cake (the goal).
When it comes to cognitive control, we know that the basics are already present in young children but that the ability increases throughout adolescence. How does that happen? Time to find out, thought researchers from the University of Pittsburgh and the University of California, Berkeley.
Don’t look at the dot
To investigate this question, the scientists recruited 195 test subjects between the ages of 10 and 26. These people had to fill in a questionnaire and their brains were scanned using fMRI.
Then, their cognitive control was put to the test with the antisaccade task. In this task, you’re asked to look at a central dot for a while. Next, another dot appears somewhere else on the screen. Here’s the catch: rather than looking at this new dot, you’re asked to look in the opposite direction. So, if the second dot appears on the left side of the central one, don’t look left. Look right instead.
In other words, you have to choose (the voluntary part) not to look at the second dot, but in the opposite direction (the goal).
And there we have it, cognitive control, tried and tested.
Two steps: organization and integration
With the results of the test and the brain scans in hand, the researchers went looking for answers.
They found that the development of cognitive control proceeds in two steps inside the brain. First, the foundation is laid early in a person’s life, before adolescence. This is reflected by the organization of brain networks. How different regions work together in networks seems to be quite stable throughout adolescence.
What does change during this period is the integration of those networks. As people mature, the ability of regions that belong to one network to communicate with regions in other networks increases. These network links, this integration, continues to increase throughout adolescence and appears to correlate with higher cognitive control.
So, cognitive control develops in two steps: one is taken early and involves the organization of the involved brain networks. The second starts later and takes a while, as it links these networks together.
One thing to note, as the authors themselves do, is that this is a cross-sectional study. That is, rather than follow people over a long time, they take a sample (a ‘cross-section’) of the population of interest. So, based on this study, it’s very hard to say how a specific person’s brain will develop. Maybe some people take these steps faster or easier than others, but answering that needs further study. Also, since the measure of integration was an average of many parts in the networks, some parts might be more involved than others. Again, more study is required.
Still, this study illustrates the importance of the integration of brain networks in the development of a full-grown cognitive control. Instead of focusing on specific brain regions in studies of self-control, it might pay to look at how all the involved networks work together.
Now, go ahead and choose to have your cake (a noble and voluntary goal).
Marek, S., Hwang, K., Foran, W., Hallquist, M., & Luna, B. (2015). The Contribution of Network Organization and Integration to the Development of Cognitive Control PLOS Biology, 13 (12) DOI: 10.1371/journal.pbio.1002328