Just by having your smartphone next to you without even using it could slow down your brain, a recent study suggests.

Researchers at the McCombs School of Business at the University of Texas at Austin conducted a study on nearly 800 people, looking at how they performed tasks when their devices were within hand reach.

The scientists found that the mere presence of your smartphone, even if it’s off, can reduce brain power.

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Study’s Experiments

In one of the experiments, participants were put in front of a computer and asked to take a series of tests that required full concentration. The individuals were told to put their devices on silent and place their smartphones on their desk face down, in their pocket or bag or outside the room. The participants were then given the tests that measured the person’s brain capability to hold and process data at any time.

In that experiment, scientists found that those with their smartphones outside of the room “significantly outperformed” those who had their devices on the desk. Those who had their gadgets outside the room also “slightly outperformed” participants who kept their smartphones in their pocket or bag.

The test suggests that by just having a smartphone near you reduces your brain power, even when they feel like they’re giving their complete attention to the task they are doing. Assistant Professor Adrian Ward, who coauthored the study, said it was a “brain drain.”

"We see a linear trend that suggests that as the smartphone becomes more noticeable, participants' available cognitive capacity decreases," Ward said in a statement. "Your conscious mind isn't thinking about your smartphone, but that process -- the process of requiring yourself to not think about something -- uses up some of your limited cognitive resources. It's a brain drain."

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In another test, scientists looked at participants’ dependence on their smartphone. The individuals did the same tests on the computer as the first round of participants, however this group was randomly instructed to keep their devices either on their desk face up, in their pocket or outside the room. For this test, some of the individuals were asked to turn their smartphone off.

Scientists learned that it didn’t matter if the smartphone was on or not, or if it was face up or face down on the desk. Just be having a cellphone nearby was enough to reduce a person’s cognitive ability because part of their brain was struggling on not to pick up or use the smartphone.

"It's not that participants were distracted because they were getting notifications on their phones," Ward said. "The mere presence of their smartphone was enough to reduce their cognitive capacity."

The study could give us some insight on why we can’t concentrate at work while our smartphones are laying in front of us at our desks. The findings comes as cellphone usage is at an all-time high, as nearly two-thirds of Americans own a smartphone, according to the Pew Research Center.