In a nutshell: The brain uses well-worn pathways to transmit information when we perform simple tasks, but it creates new pathways in response to more difficult tasks.

View Paper Abstract

Think about your daily commute: there are many roads that could get you from A to B, but you likely take the same route each day, probably because it’s the most direct or efficient way. The set of elements, or roads, that you use is much smaller than the total set available to you.

Brain activity is much the same. Although there are many different pathways that brain cells could use to communicate with one another, they tend to favour a smaller subset of the total number of available pathways. Relying on this subset of pathways helps the brain to carry out tasks quickly, without having to learn from scratch every time.

But what happens when the brain has to deal with a really complicated or challenging task? Do the patterns of brain activity change in response? And if so, how?

To answer these questions, Brain Function CoE investigators James (Mac) Shine, Luke Hearne, Michael Breakspear and Jason Mattingley collaborated with colleagues in Australia and the USA.

The researchers recruited 60 participants who completed the Latin Squares Task, a Sudoku-like puzzle in which cells in a grid are filled with particular shapes so that no row or column contains more than one of each shape. The researchers varied the difficulty of the task and used magnetic resonance imaging (MRI) to measure the participants’ brain activity while they completed it.

They found that as the task became more difficult to complete, the patterns of brain activity changed. And as the patterns changed, participants were more likely to make mistakes on the Latin Squares Task.

It’s just as if you altered your commute to avoid unexpected traffic, taking the back roads to reach your destination. In unfamiliar territory, you’d be more likely to take a wrong turn.

The high-resolution MRI used in the experiment also enabled the researchers to pinpoint the region of the brain responsible for bypassing established patterns and creating new ones when necessary. They found that the thalamus is our brain’s own satnav system. This small structure in the centre of the brain, which is connected to almost every other region, helps to direct (and redirect) the flow of information in the brain.

Next steps:
The researchers are interested to see whether the same changes in the patterns of brain activity happen over time as we learn, or in response to different neurodegenerative and neurodevelopmental disorders.

Shine, J.M., Hearne, L.J., Breakspear, M., Hwang, K., Muller, E.J., Sporns, O., Poldrack, R.A., Mattingley, J.B., & Cocchi, L. (2019). The low-dimensional neural architecture of cognitive complexity is related to activity in medial thalamic nuclei. Neuron. doi: 10.1016/j.neuron.2019.09.002

Republish this article:

We believe in sharing knowledge. We use a Creative Commons Attribution 4.0 International License, which allows unrestricted use of this content, subject only to appropriate attribution. So please use this article as is, or edit it to fit your purposes. Referrals, mentions and links are appreciated.