Mental Health

Feeling Distracted? Your Focus Dips Four Times Per Second, Study Finds

Are you focusing exclusively on this sentence? 

Spoiler: You are not, and you can thank the neuron activity in your brain for that.

After two studies examined both monkeys (macaques) and human beings in similar setups, researchers discovered our attention is not as fluid as we believe it to be, acting less like a spotlight and more like a strobe.

Your brain does not "unfocus" per se but merely conducts a check on your surrounding to see if it should focus on something else, explained Ian Fiebelkorn, who worked on the macaque-focused study and is a cognitive neuroscientist at Princeton University. 

This type of "pulsing attention" can be considered as an evolutionary advantage, most likely to help us stay on guard from any potential threat even if our primary focus is on a completely different thing.

"It’s like if you’re going after this shiny red apple in a tree, you want to know if something bigger or with sharper teeth is also going for that apple," Fiebelkorn said. "Yeah, you’re focused on the apple. But not so focused you don’t see danger coming."

According to Gizmodo, the two studies involved human beings and monkeys focusing on a screen. The researchers monitored their brain activity with the help of electrodes and also used a camera to track their eye movements. 

The subjects were instructed to pull down a lever or let go of the computer mouse if they noticed a brief flashing of a shape on screen (it was a very faint and nearly undetectable rectangle). By examining their brains, researchers found both the monkeys and the human subjects experienced similar dips in neuron activity — specifically, four times per second.

This meant your brain was designed to check on your surroundings four times per second, allowing us to have the opportunity to switch our attention once every 250 milliseconds. And the trait is likely not limited to the brains of humans and macaques but potentially other species.

Understanding these two states of the brain — focus and distraction — could help researchers in finding more effective ways to tackle attention deficit hyperactivity disorder (ADHD).

"Whether you are talking about the hyper-focused type of ADHD or the distractible type, you can easily draw a parallel with the two states that normal brains alternate between," said author Sabine Kastner, who is also cognitive neuroscientist at Princeton. "It could be that brains affected by ADHD are unable to balance between the two attentional spaces and instead get locked into one or the other."

The two studies, one using human subjects and another using animal subjects, were published in Neuron on Aug. 22. The back-to-back papers were titled "Neural Mechanisms of Sustained Attention Are Rhythmic" and "A Dynamic Interplay within the Frontoparietal Network Underlies Rhythmic Spatial Attention" respectively.