Your smartphone could be responsible for your IQ.

By Mike Huyhn


Posted on September 30, 2019

Grab your smartphone for a second. Now open all the apps and windows and log yourself out. Proceed to delete the number of your ex and in-laws. The next part is the most important: place the top left corner of your phone between your thumb and index finger, carefully hover it over a flaming trash can and let it go. Step back from the trash can, turn around and walk away.

Congratulations, you’re now roughly 20% smarter. Okay, we didn’t have to be so dramatic but that’s essentially the summary of a recent study which found picking up your phone whilst engaging in mentally challenging tasks was detrimental to your brain’s mental performance. More specifically the distracting act of using a smartphone mid-task was found to handicap the brain’s ability to recharge.

“Cellphones may have this affect because even just seeing your phone activates thoughts of checking messages, connecting with people, access to ever-refilling information and more, in ways that are different than how we use other screens like computers, and laptops,” explains Terri Kurtzberg, the study’s co-author and associate professor of management and global business at Rutgers Business School.

Kurtzberg and her team came to this conclusion in a study which involved 400 college students tasked with solving difficult word puzzles. Midway through the mentally intensive task the students were split into control groups. Most were allowed to use their phones in the break whilst others were only allowed to use a computer, read a print circular or have no break at all.

The results revealed that students who used their phones during the break experienced the highest level of mental drain when compared to others. When it came time to getting back on track, the phone using group took 19% longer to finish tasks and solved 22% less problems than all the other groups in total. This poor result in mental efficiency and processing speed was also on par with the group that took no break at all.

But why is this lapse in mental performance happening to phone users and not computer users?

The researchers believe that smartphones are attention portals into a larger landscape of attention-seeking platforms. In other words there are multiple layers in smartphones all vying to draw our mental energy in different directions. When paired with the modern phone user’s chronic underestimation of how much energy drain a smartphone can cause alongside the overestimation of the brain’s processing capacity, mental lethargy is bound to happen.

This drives home a further argument in that not all distractions are perceived equal by the human mind. Some tend to draw more of our attention and drain more energy, subsequently affecting our overall mental performance. Proving phones in the modern age are no longer just devices and more of a life companion, the study concludes it “supports the developing theory that people are more cognitively and emotionally attached to their phones than they are to other devices, including other electronic tools such as computers”.

“It is important to know the costs associated with reaching for this device during every spare minute,” says Kurtzberg.

“We assume it’s no different from any other break – but the phone may carry increasing levels of distraction that make it difficult to return focused attention to work tasks.”

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