Having your smartphone nearby takes a toll on your thinking

From Harvard Business Review, Tuesday, March 20, 2018, See
Having Your Smartphone Nearby Takes a Toll on Your Thinking

By Kristen Duke, Adrian Ward, Ayelet Gneezy, and Maarten Bos

In recent research [SEE https://www.journals.uchicago.edu/doi/full/10.1086/691462 ], we investigated whether merely having one's own smartphone nearby could influence cognitive abilities. In two lab experiments, nearly 800 people completed tasks designed to measure their cognitive capacity. In one task, participants simultaneously completed math problems and memorized random letters. This tests how well they can keep track of task-relevant information while engaging in a complex cognitive task. In the second task, participants saw a set of images that formed an incomplete pattern, and chose the image that best completed the pattern. This task measures "fluid intelligence," or people's ability to reason and solve novel problems. Performance on both of these tasks is affected by individuals' available mental resources.


The results were striking: individuals who completed these tasks while their phones were in another room performed the best, followed by those who left their phones in their pockets. In last place were those whose phones were on their desks. We saw similar results when participants' phones were turned off: people performed worst when their phones were nearby, and best when they were away in a separate room. Thus, merely having their smartphones out on the desk led to a small but statistically significant impairment of individuals' cognitive capacity -- on par with effects of lacking sleep. [SEE https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2699161/ ]

This cognitive capacity is critical for helping us learn, reason, and develop creative ideas. [SEE https://www.ncbi.nlm.nih.gov/pubmed/15149250 ] In this way, even a small effect on cognitive capacity can have a big impact, considering the billions of smartphone owners who have their devices present at countless moments of their lives. This means that in these moments, the mere presence of our smartphones can adversely affect our ability to think and problem-solve - even when we aren't using them. Even when we aren't looking at them. Even when they are face-down. And even when they are powered off altogether.

Why are smartphones so distracting, even when they're not buzzing or chirping at us? The costs of smartphones are inextricably linked to their benefits. The immense value smartphones provide, as personal hubs connecting us to each other and to virtually all of the world's collective knowledge, necessarily positions them as important and relevant to myriad aspects of our everyday lives. Research in cognitive psychology shows that humans learn to automatically pay attention to things that are habitually relevant to them, even when they are focused on a different task. [SEE http://psycnet.apa.org/record/1977-20305-001 ] For example, even if we are actively engaged in a conversation, we will turn our heads when someone says our name across the room. [SEE https://www.tandfonline.com/doi/abs/10.1080/17470215908416289 ] Similarly, parents automatically attend to the sight or sound of a baby's cry. [SEE https://onlinelibrary.wiley.com/doi/full/10.1111/desc.12090 AND http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0154283 ]

Our research suggests that, in a way, the mere presence of our smartphones is like the sound of our names - they are constantly calling to us, exerting a gravitational pull on our attention. If you have ever felt a "phantom buzz" you inherently know this. [SEE https://www.npr.org/sections/alltechconsidered/2013/09/30/226820044/phantom-phone-vibrations-so-common-they-ve-changed-our-brains ] Attempts to block or resist this pull takes a toll by impairing our cognitive abilities. In a poignant twist, then, this means that when we are successful at resisting the urge to attend to our smartphones, we may actually be undermining our own cognitive performance.


Our data also show that the negative impact of smartphone presence is most pronounced for individuals who rank high on a measure capturing the strength of their connection to their phones -- that is, those who strongly agree with statements such as "I would have trouble getting through a normal day without my cell phone" and "It would be painful for me to give up my cell phone for a day." In a world where people continue to increasingly rely on their phones, it is only logical to expect this effect to become stronger and more universal.

We are clearly not the first to take note of the potential costs of smartphones. Think about the number of fatalities associated with driving while talking on the phone or texting, or of texting while walking. [SEE https://www.edgarsnyder.com/car-accident/cause-of-accident/cell-phone/cell-phone-statistics.html ] and https://www.usatoday.com/story/news/2016/03/08/pedestrian-fatalities-surge-10-percent/81483294/ ] Even hearing your phone ring while you're busy doing something else can boost your anxiety. [SEE https://onlinelibrary.wiley.com/doi/abs/10.1111/jcc4.12109 ] Knowing we have missed a text message or call leads our minds to wander, which can impair performance on tasks that require sustained attention and undermine our enjoyment. Beyond these cognitive and health-related consequences, smartphones may impair our social functioning: having your smartphone out can distract you during social experiences and make them less enjoyable. [SEE https://www.ncbi.nlm.nih.gov/pubmed/26121498 AND https://www.ncbi.nlm.nih.gov/pubmed/27608068 AND https://www.sciencedirect.com/science/article/pii/S0022103117301737 ] ]



Smartphones have distinct uses. There are situations in which our smartphones provide a key value, such as when they help us get in touch with someone we're trying to meet, or when we use them to search for information that can help us make better decisions. Those are great moments to have our phones nearby. But, rather than smartphones taking over our lives, we should take back the reigns: when our smartphones aren't directly necessary, and when being fully cognitively available is important, setting aside a period of time to put them away-in another room-can be quite valuable.

Ayelet Gneezy is an Associate Professor of Behavioral Sciences and Marketing at the Rady School of Management, University of California, San Diego. Her research focuses on consumers' judgment and decision-making, prosocial and charitable behavior, and behavior change.