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Smartphones may be changing the way we think

Those attention-grabbing digital devices are like a new appendage. How are they changing us?

12:21pm, March 17, 2017
young adults on smartphones

DIGITAL MINDS  Smartphones offer ways to connect, store data and get directions. But what exactly digital tech does to our brains is still an unanswered question. 

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Not too long ago, the internet was stationary. Most often, we’d browse the Web from a desktop computer in our living room or office. If we were feeling really adventurous, maybe we’d cart our laptop to a coffee shop. Looking back, those days seem quaint.

Today, the internet moves through our lives with us. We hunt Pokémon as we shuffle down the sidewalk. We text at red lights. We tweet from the bathroom. We sleep with a smartphone within arm’s reach, using the device as both lullaby and alarm clock. Sometimes we put our phones down while we eat, but usually faceup, just in case something important happens.

Our iPhones, Androids and other smartphones have led us to effortlessly adjust our behavior. Portable technology has overhauled our driving habits, our dating styles and even our posture. Despite the occasional headlines claiming that digital technology is rotting our brains, not to mention what it’s doing to our children, we’ve welcomed this alluring life partner with open arms and swiping thumbs.

Scientists suspect that these near-constant interactions with digital technology influence our brains. Small studies are turning up hints that our devices may change how we remember, how we navigate and how we create happiness — or not.



Portion of Americans who reported using a technology device in the hour before bedtime

Source: Michael Gradisar et al/J. Clin. Sleep Med. 2013



Portion of U.S. college students who reported checking their phones at least once overnight

Source: L. Rosen et al/Sleep Health 2016

Somewhat limited, occasionally contradictory findings illustrate how science has struggled to pin down this slippery, fast-moving phenomenon. Laboratory studies hint that technology, and its constant interruptions, may change our thinking strategies. Like our husbands and wives, our devices have become “memory partners,” allowing us to dump information there and forget about it — an off-loading that comes with benefits and drawbacks. Navigational strategies may be shifting in the GPS era, a change that might be reflected in how the brain maps its place in the world. Constant interactions with technology may even raise anxiety in certain settings.

Yet one large study that asked people about their digital lives suggests that moderate use of digital technology has no ill effects on mental well-being.

The question of how technology helps and hinders our thinking is incredibly hard to answer. Both lab and observational studies have drawbacks. The artificial confines of lab experiments lead to very limited sets of observations, insights that may not apply to real life, says experimental psychologist Andrew Przybylski of the University of Oxford. “This is a lot like drawing conclusions about the effects of baseball on players’ brains after observing three swings in the batting cage.”

Observational studies of behavior in the real world, on the other hand, turn up associations, not causes. It’s hard to pull out real effects from within life’s messiness. The goal, some scientists say, is to design studies that bring the rigors of the lab to the complexities of real life, and then to use the resulting insights to guide our behavior. But that’s a big goal, and one that scientists may never reach.

Evolutionary neurobiologist Leah Krubitzer is comfortable with this scientific ambiguity. She doesn’t put a positive or negative value on today’s digital landscape. Neither good nor bad, it just is what it is: the latest iteration on the continuum of changing environments, says Krubitzer, of the University of California, Davis.

“I can tell you for sure that technology is changing our brains,” she says. It’s just that so far, no one knows what those changes mean.

Of course, nearly everything changes the brain. Musical training reshapes parts of the brain. Learning the convoluted streets of London swells a mapmaking structure in the brains of cabbies. Even getting a good night’s sleep changes the brain. Every aspect of our environment can influence brain and behaviors. In some ways, digital technology is no different. Yet some scientists suspect that there might be something particularly pernicious about digital technology’s grip on the brain.

“We are information-seeking creatures,” says neuroscientist Adam Gazzaley of the University of California, San Francisco. “We are driven to it in very powerful ways.” Today’s digital tools give us unprecedented exposure to information that doesn’t wait for you to seek it out; it seeks you out, he says. That pull is nearly irresistible.

Despite the many unanswered questions about whether our digital devices are influencing our brains and behaviors, and whether for good or evil, technology is galloping ahead. “We should have been asking ourselves [these sorts of questions] in the ’70s or ’80s,” Krubitzer says. “It’s too late now. We’re kind of closing the barn doors after the horses got out.”

Story continues after graphic


A team in the United Kingdom designed an Android app to track cell phone use in students and staff at the University of Lincoln for 15 days. The app registered when the phone’s screen turned on and then off, resulting in charts like the one below depicting one moderate cell phone user's daily activity. Wider bars mean longer time on phone. Alarm clock wake-ups on weekdays are obvious. Saturdays are marked by red dashed line.


Attention grabber

One way in which today’s digital technology is distinct from earlier advances (like landline telephones) is the sheer amount of time people spend with it. In just a decade, smartphones have saturated the market, enabling instant internet access to an estimated 2 billion people around the world. In one small study reported in 2015, 23 adults, ages 18 to 33, spent an average of five hours a day on their phones, broken up into 85 distinct daily sessions. When asked how many times they thought they used their phones, participants underestimated by half.

In a different study, Larry Rosen, a psychologist at California State University, Dominguez Hills, used an app to monitor how often college students unlocked their phones. The students checked their phones an average of 60 times a day, each session lasting about three to four minutes for a total of 220 minutes a day. That’s a lot of interruption, Rosen says.

What am I missing?

In one small study of 104 college students, more than half unlocked their phones more than 60 times a day. 

Source: L. Rosen

Smartphones are “literally omnipresent 24-7, and as such, it’s almost like an appendage,” he says. And often, we are compelled to look at this new, alluring rectangular limb instead of what’s around us. “This device is really powerful,” Rosen says. “It’s really influencing our behavior. It’s changed the way we see the world.”

Technology does that. Printing presses, electricity, televisions and telephones all shifted people’s habits drastically, Przybylski says. He proposes that the furor over digital technology melting brains and crippling social lives is just the latest incarnation of the age-old fear of change. “You have to ask yourself, ‘Is there something magical about the power of an LCD screen?’ ” Przybylski says.

Yet some researchers suspect that there is something particularly compelling about this advance. “It just feels different. Computers and the internet and the cloud are embedded in our lives,” says psychologist Benjamin Storm of the University of California, Santa Cruz. “The scope of the amount of information we have at our fingertips is beyond anything we’ve ever experienced. The temptation to become really reliant on it seems to be greater.”

Memory outsourcing

Our digital reliance may encourage even more reliance, at least for memory, Storm’s work suggests. Sixty college undergraduates were given a mix of trivia questions — some easy, some hard. Half of the students had to answer the questions on their own; the other half were told to use the internet. Later, the students were given an easier set of questions, such as “What is the center of a hurricane called?” This time, the students were told they could use the internet if they wanted.

People who had used the internet initially were more likely to rely on internet help for the second, easy set of questions, Storm and colleagues reported online last July in Memory. “People who had gotten used to using the internet continued to do so, even though they knew the answer,” Storm says. This kind of overreliance may signal a change in how people use their memory. “No longer do we just rely on what we know,” he says.

MRI scans of hippocampus and caudate nucleus That work builds on results published in a 2011 paper in Science. A series of experiments showed that people who expected to have access to the internet later made less effort to remember things. In this way, the internet has taken the place formerly filled by spouses who remember birthdays, grandparents who remember recipes and coworkers who remember the correct paperwork codes — officially known as “transactive memory partners.”

“We are becoming symbiotic with our computer tools,” Betsy Sparrow, then at Columbia University, and colleagues wrote in 2011. “The experience of losing our internet connection becomes more and more like losing a friend. We must remain plugged in to know what Google knows.”

That digital crutch isn’t necessarily a bad thing, Storm points out. Human memory is notoriously squishy, susceptible to false memories and outright forgetting. The internet, though imperfect, can be a resource of good information. And it’s not clear, he says, whether our memories are truly worse, or whether we perform at the same level, but just reach the answer in a different way.

“Some people think memory is absolutely declining as a result of us using technology,” he says. “Others disagree. Based on the current data, though, I don’t think we can really make strong conclusions one way or the other.”

The potential downsides of this memory outsourcing are nebulous, Storm says. It’s possible that digital reliance influences — and perhaps  even weakens — other parts of our thinking. “Does it change the way we learn? Does it change the way we start to put information together, to build our own stories, to generate new ideas?” Storm asks. “There could be consequences that we’re not necessarily aware of yet.”

Research by Gazzaley and others has documented effects of interruptions and multitasking, which are hard to avoid with incessant news alerts, status updates and Instagrams waiting in our pockets. Siphoning attention can cause trouble for a long list of thinking skills, including short- and long-term memory, attention, perception and reaction time. Those findings, however, come from experiments in labs that ask a person to toggle between two tasks while undergoing a brain scan, for instance. Similar effects have not been as obvious for people going about their daily lives, Gazzaley says. But he is convinced that constant interruptions — the dings and buzzes, our own restless need to check our phones — are influencing our ability to think.

Making maps

Consequences of technology are starting to show up for another cognitive task — navigating, particularly while driving. Instead of checking a map and planning a route before a trip, people can now rely on their smartphones to do the work for them. Anecdotal news stories describe people who obeyed the tinny GPS voice that instructed them to drive into a lake or through barricades at the entrance of a partially demolished bridge. Our navigational skills may be at risk as we shift to neurologically easier ways to find our way, says cognitive neuroscientist Véronique Bohbot of McGill University in Montreal.

Historically, getting to the right destination required a person to have the lay of the land, a mental map of the terrain. That strategy takes more work than one that’s called a “response strategy,” the type of navigating that starts with an electronic voice command. “You just know the response — turn right, turn left, go straight. That’s all you know,” Bohbot says. “You’re on autopilot.”

Google begets Google

Compared with people who had to rely on memory (blue bars) to answer an initial mix of easy and hard trivia questions, people who used Google to find answers (red bars) were more likely to use Google for a second, easy set of questions. Inconvenience (having to get up from the sofa to walk to a computer or an iPod Touch) didn’t stop the Googling.

Source: B.C. Storm, S.M. Stone and A.S. Benjamin/Memory 2016

A response strategy is easier, but it leaves people with less knowledge. People who walked through a town in Japan with human guides did a better job later navigating the same route than people who had walked with GPS as a companion, researchers have found.

Scientists are looking for signs that video games, which often expose people to lots of response-heavy situations, influence how people get around. In a small study, Bohbot and colleagues found that people who average 18 hours a week playing action video games such as Call of Duty navigated differently than people who don’t play the games. When tested on a virtual maze, players of action video games were more likely to use the simpler response learning strategy to make their way through, Bohbot and colleagues reported in 2015 in Proceedings of the Royal Society B.

That easier type of response navigation depends on the caudate nucleus, a brain area thought to be involved in habit formation and addiction. In contrast, nerve cells in the brain’s hippocampus help create mental maps of the world and assist in the more complex navigation. Some results suggest that people who use the response method have bigger caudate nuclei, and more brain activity there. Conversely, people who use spatial strategies that require a mental map have larger, busier hippocampi.

Those results on video game players are preliminary and show an association within a group that may share potentially confounding similarities. Yet it’s possible that getting into a habit of mental laxity may change the way people navigate. Digital technology isn’t itself to blame, Bohbot says. “It’s not the technology that’s necessarily good or bad for our brain. It’s how we use the technology,” she says. “We have a tendency to use it in the way that seems to be easiest for us. We’re not making the effort.”

Parts of the brain, including those used to navigate, have many jobs. Changing one aspect of brain function with one type of behavior might have implications for other aspects of life. A small study by Bohbot showed that people who navigate by relying on the addiction-related caudate nucleus smoke more cigarettes, drink more alcohol and are more likely to use marijuana than people who rely on the hippocampus. What to make of that association is still very much up in the air.

Sweating the smartphone

Other researchers are trying to tackle questions of how technology affects our psychological outlooks. Rosen and colleagues have turned up clues that digital devices have become a new source of anxiety for people.



Portion of 14- to 18-year-olds who reported always or almost always texting while watching TV

Source: Deloitte 2016 Digital Democracy Survey

In diabolical experiments, Cal State’s Rosen takes college students’ phones away, under the ruse that the devices are interfering with laboratory measurements of stress, such as heart rate and sweating. The phones are left on, but placed out of reach of the students, who are reading a passage. Then, the researchers start texting the students, who are forced to listen to the dings without being able to see the messages or respond. Measurements of anxiety spike, Rosen has found, and reading comprehension dwindles.

Other experiments have found that heavy technology users last about 10 minutes without their phones before showing signs of anxiety.

Fundamentally, an interruption in smartphone access is no different from those in the days before smartphones, when the landline rang as you were walking into the house with bags full of groceries, so you missed the call. Both situations can raise anxiety over a connection missed. But Rosen suspects that our dependence on digital technology causes these situations to occur much more often.

“The technology is magnificent,” he says. “Having said that, I think that this constant bombardment of needing to check in, needing to be connected, this feeling of ‘I can’t be disconnected, I can’t cut the tether for five minutes,’ that’s going to have a long-term effect.”

The question of whether digital technology is good or bad for people is nearly impossible to answer, but a survey of 120,000 British 15-year-olds (99.5 percent reported using technology daily) takes a stab at it. Oxford’s Przybylski and Netta Weinstein at Cardiff University in Wales have turned up hints that moderate use of digital technology — TV, computers, video games and smartphones — correlates with good mental health, measured by questions that asked about happiness, life satisfaction and social activity.

When the researchers plotted technology use against mental well-being, an umbrella-shaped curve emerged, highlighting what the researchers call the “Goldilocks spot” of technology use — not too little and not too much.

“We found that you’ve got to do a lot of texting before it hurts,” Przybylski says. For smartphone use, the shift from benign to potentially harmful came after about two hours of use on weekdays, mathematical analyses revealed. Weekday recreational computer use had a longer limit: four hours and 17 minutes, the researchers wrote in the February Psychological Science.

Story continues after graphs

Screen age

British teenagers’ mental well-being, based on a 14-question survey about happiness and life satisfaction, seemed to shift with hours spent using digital media. Scores averaged between 40 and 50. Each type of media had a sweet spot, suggesting that moderate digital technology use may have benefits.

Source: A.K. Przybylski and N. Weinstein/Psychological Science 2017

For even the heaviest users, the relationship between technology use and poorer mental health wasn’t all that strong. For scale, the potential negative effects of all that screen time was less than a third of the size of the positive effects of eating breakfast, Przybylski and Weinstein found.

Even if a relationship is found between technology use and poorer mental health, scientists still wouldn’t know why, Przybylski says. Perhaps the effect comes from displacing something, such as exercise or socializing, and not the technology itself.

We may never know just how our digital toys shape our brains. Technology is constantly changing, and fast. Our brains are responding and adapting to it.

“The human neocortex basically re-creates itself over successive generations,” Krubitzer says. It’s a given that people raised in a digital environment are going to have brains that reflect that environment. “We went from using stones to crack nuts to texting on a daily basis,” she says. “Clearly the brain has changed.”

It’s possible that those changes are a good thing, perhaps better preparing children to succeed in a fast-paced digital world. Or maybe we will come to discover that when we no longer make the effort to memorize our best friend’s phone number, something important is quietly slipping away.

This article appears in the April 1, 2017, issue of Science News with the headline, "Digital minds: Are smartphones changing our brains?"


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Further Reading

L. Sanders. A ban on screens in bedroom may save kids’ sleep. Science News Online. January 23, 2017.

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