Study: Inability to focus is not a sign of less intelligence

Passengers on the five-hour bus journey either use it to take in some of the sights of Hong Kong or get some much-needed sleep – Copyright AFP Bertha WANG

If you are not able to complete the reading of this article without being distracted or zoning out do not be too alarmed, at least when it comes to questions about your relative cognitive abilities.

A new study from Brown University provides new insights into the brain mechanisms that help people pay attention amid such distraction, as well as what is happening when someone struggles to focus, especially when there are competing environmental distractions.

We each are able to people can separately control how much they focus (by enhancing relevant information) and how much they filter (by tuning out distraction). Hence there are big differences between individuals in a given population.

For the research, scientists administered a cognitive task to participants while measuring their brain activity in a functional magnetic resonance imaging (fMRI) machine. The participants saw a swirling mass of green and purple dots moving left and right, like a swarm of fireflies.

In terms of what is happening in within the brain, the intraparietal sulcus is performing two activities: one part adjusts focusing and one that adjusts filtering. Another region, the anterior cingulate cortex tracks what’s going on with the dots. This part of the brain deals with perceptual-motor coordination.

When the anterior cingulate cortex recognizes that, for instance, motion is making the task more difficult, it directs the intraparietal sulcus to adjust the filtering in order to reduce the sensitivity to motion. This brain region is involved in certain higher-level functions, including attention allocation, reward anticipation, decision-making, impulse control (such as performance monitoring and error detection), and emotion.

The tasks set for the subjects, which varied in difficulty, involved distinguishing between the movement and colours of the dots.

For example, participants in one exercise were instructed to select which colour was in the majority for the rapidly moving dots when the ratio of purple to green was almost 50/50.

The researchers says this demonstrates the humans possess tremendous cognitive flexibility — to pay attention to what we want, when we want to.

In terms of the different outcomes, the researchers point out the distinction between the importance of mental coordination over mental capacity. These are different concepts entirely.

The psychological research appears in the journal Nature Human Behavior, titled “Orthogonal neural encoding of targets and distractors supports multivariate cognitive control.”