How Much Smartphone Use Is Too Much?

iStock
iStock

Since the iPhone debuted in 2007, ushering in the age of the phone-as-computer, smartphone use has exploded worldwide, with an estimated 2.3 billion users last year. According to a 2016 Pew Research survey, 77 percent of Americans own a smartphone, and other recent stats have found that users are on their phones an average of more than five hours per day—almost double the rate in 2013. More people now use a mobile device to get online than they do a computer. This is especially true in regions where people may not be able to afford a personal computer but can buy a smartphone.

We love our smartphones perhaps a little too much, and the desire to unplug is growing among people who see 24/7 connectedness as damaging to their mental health. This week, Apple announced new iPhone features meant to curb our dependence on our devices, including a weekly "Report" app that shows your phone and app usage, as well as how many times you physically pick up your phone. (One small study by the consumer research firm Dscout found that we touch our phones more than 2600 times a day.) You can also set customized limits for overall phone usage with the "Screen Time" app.

Many of us feel anxiety at the very thought of being without their phone and the access it offers to the internet. Researchers have a term for it: nomophobia ("no mobile phone phobia"). So how much smartphone use is too much?

That turns out to be a surprisingly difficult question to answer. "Smartphone addiction" isn't an official medical diagnosis. Even the experts haven't decided how much is too much—or even whether smartphone addiction is real.

DEFINING ADDICTION

To understand what's going on, we have to first step back and define what addiction is. It's different from habits, which are subconsciously performed routines, and dependence, when repeated use of something causes withdrawals when you stop. You can be dependent on something without it ruining your life. Addiction is a mental disorder characterized by compulsive consumption despite serious adverse consequences.

Yet, our understanding of behavioral addictions—especially ones that don't involve ingesting mind-altering chemicals—is still evolving. Actions that result in psychological rewards, such as a crushing a castle in Clash Royale or getting a new ping from Instagram, can turn compulsive as our brains rewire to seek that payoff (just like our smartphones, our brains use electricity to operate, and circuits of neurons can restructure to skew toward rewards). For a minority of people, it seems those compulsions can turn to addictions.

Psychologists have been treating internet addiction for almost as long as the internet has been around: Kimberly Young, a clinical psychologist and program director at St. Bonaventure University, founded the Center for Internet Addiction back in 1995. By 2013, addictive behavior connected to personal technology was common enough that in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), the bible for mental disorder diagnoses, the American Psychiatric Association included "internet gaming disorder" as a condition "warranting further study." These days, thanks to an abundance of horror stories involving people who were glued to the internet until they died—and living gamers who are so engrossed in their games that they ignore paramedics removing dead gamers—internet rehabs are popping up all over the world.

But in virtually all of the medical literature published so far about internet addiction—including the WHO's forthcoming 11th edition of International Classification of Diseases (ICD-11), whose "excessive use of the internet" is built around how much gaming interferes with daily life—there's no mention of smartphones.

According to Marc Potenza, a professor of psychiatry and neuroscience at the Yale School of Medicine, there's a reason for these omissions: Despite the official definitions included in the DSM-V and ICD-11, "there's debate regarding the use of those terms [internet addiction]. Both the ICD-11 group and the DSM-V group chose to focus on the behavior rather than the delivery device."

So while you may feel nomophobia when you can't find your internet "delivery device," the global psychiatric community thinks it's the internet itself that's the problem—not the phone in your hand.

THE REWARDS THAT COME FROM OUR PHONES

We are getting something from our phones, though, and it's not just access to the internet. Receiving a notification gives us a small dopamine burst, and we learn to associate that dose of pleasure with the smartphone. You may pull your phone from your pocket a dozen times an hour to check for notifications—even if you know they're not there because your phone would have, well, notified you.

It's not unusual for people to become attached to an action (checking the phone) rather than its reward (getting a notification). Sometimes smokers trying to quit feel the urge to chew or bite and need to replace cigarettes with gum or sunflower seeds. According to Stephanie Borgland, a neuroscientist and associate professor at University of Calgary, this is called a Pavlovian-instrumental transfer—a reference to Ivan Pavlov's experiments, in which he reinforced behavior in dogs through signals and rewards. Borgland tells Mental Floss that we can become compulsively attached to the cues of phone use. We cling to the physical stimuli our brains have linked to the reward.

There may be an evolutionary basis to this behavior. Like other primates, humans are social mammals, but we have dramatically higher levels of dopamine than our cousins. This neurotransmitter is associated with reward-motivated behavior. So when we get a notification on an app that tells us someone has engaged us in social interaction—which we naturally crave—it triggers our natural inclinations.

HOW TO CURB YOUR ENTHUSIASM (FOR YOUR PHONE)

The global psychiatric community may not be convinced our smartphones are a problem, and no one has died from checking Snapchat too often—or at least it hasn't been reported. But most of us would say that spending five hours a day on our smartphones is too much. So are there any guidelines?

At this stage of research into smartphone use, there are no specific time-limit recommendations, though some researchers are working on a smartphone addiction scale; one was proposed in a 2013 study in the journal PLOS One. Based on what's said to be coming out in the ICD-11, here's one simple guideline: Problematic smartphone use negatively interferes with your life. Some research suggests Facebook, Instagram, and even online gaming make us feel more isolated and less connected. The more we try to fill that hole by tapping away at our phones, the more we crave social interaction. "There are a number of factors that have been associated with these behaviors or conditions," says Potenza, who is developing tools to screen for and assess problematic internet use and has consulted with the WHO on these issues. "And arguably one of the most consistent ones is depression."

One way to assess whether your smartphone is a problem is noting how you react when you're cut off from it, according to the PLOS One study. The study proposed a "smartphone addiction scale" based on negative responses to being without a smartphone, among other criteria. What happens on a day when you accidentally leave it at home? Are you irritable or anxious? Do you feel isolated from friends or unsafe? Do you have trouble concentrating on work, school, or other important responsibilities, whether or not you have your phone?

While smartphones may not be truly addictive in a medical sense, learning how to use them in a more mindful, healthy manner couldn't hurt. Test yourself for nomophobia [PDF]—knowing how much time you spend online is the first step to identifying how that can be problematic. Block distracting sites or track usage via a timer or an app (beware third-party apps' privacy settings, however). Delete the apps that keep the phone in your hand even when you're not online, like games. If you're still struggling, you could ditch smartphones altogether and downgrade to a "dumb" phone or get a Light Phone, a cellular device "designed to be used as little as possible."

A recent WIRED feature argued that using the internet five hours per day isn't a personal failing so much as a reflection of the way many apps are purposely designed to keep you salivating for more. So perhaps the best measure is to leave your phone behind once in a while. Schedule a screen-free Sunday. Go for a walk in the woods. Meditate. Socialize instead of binging The Office again. Don’t worry—you’ll be fine.

This Puzzle Teaches Kids—and Adults—About Amazing Women Scientists

This 500-piece puzzle sold on Amazon celebrates the achievements of women in STEM fields.
This 500-piece puzzle sold on Amazon celebrates the achievements of women in STEM fields.
Clarkson Potter/Amazon

It’s no secret female scientists have been overlooked for decades, but this puzzle, which sells for $17 on Amazon, aims to rectify that by spotlighting 15 notable women who made incredible strides in STEM fields.

The puzzle is the work of illustrator Rachel Ignotofsky, author of the best-selling picture book Women in Science: 50 Fearless Pioneers Who Changed the World. “The most important way to fight gender bias is to share stories of amazing women with boys and girls,” Ignotofsky told Mental Floss in 2016. “Many of these women have changed the way that we understand our world forever, but we don’t know about them. Steve Jobs and Bill Gates are more household names than Grace Hopper, who invented coding. When we don’t tell these stories, we allow these inequalities and stereotypes to continue.”

The 500-piece puzzle features Grace Hopper along with several other notable scientists, including astronaut Mae Jemison, particle physicist Sau Lan Wu, and Nobel Prize-winning cytogeneticist Barbara McClintock.

Ignotofsky hopes the puzzle, as well as the book it’s based on, will inspire children and adults alike. “My hope is that seeing these women who have led in the past will help girls feel more confident, like ‘Not only do I deserve this, but I’m going to take it,’” she said.

At Mental Floss, we only write about the products we love and want to share with our readers, so all products are chosen independently by our editors. Mental Floss has affiliate relationships with certain retailers and may receive a percentage of any sale made from the links on this page. Prices and availability are accurate as of the time of publication.

It’s Easy Being Green: Most Amphibians Are Biofluorescent, Study Finds

An alpine newt glows green after being exposed to blue light.
An alpine newt glows green after being exposed to blue light.
Jennifer Y. Lamb and Matthew P. Davis

If you walk through a forest at night, you see only darkness and shadows, and perhaps the smudgy outline of trees against the sky. But if you were a salamander snuggled in the leaf litter, under the right light conditions, you might see something completely different: foliage glimmering in shades of red, and your fellow amphibians glowing in brilliant greens.

Biofluorescence—in which animals emit a fluorescent glow after absorbing high-energy wavelengths of light—is likely widespread among most, if not all, amphibians, according to a new study published in the journal Scientific Reports. Previously, only one species of salamander and three frog species were known to biofluoresce.

Alpine newt under white light
The same view of an alpine newt under white light
Jennifer Y. Lamb and Matthew P. Davis

“I do field work, so I’m out there capturing species of amphibians, and I think, ‘huh, I wonder if this fluoresces,’” says Jennifer Y. Lamb, an assistant professor of biology at St. Cloud State University in Minnesota. She and co-author Matthew P. Davis, an assistant professor at the university, collected representatives from eight of the 10 salamander families, five families of frogs, and one family of caecelians, a type of limbless amphibian. They exposed each critter to high-energy blue light and then viewed them through a yellow filter to see if and how they glowed.

“One of the first salamanders we tested was the Eastern tiger salamander. We saw that it fluoresced really brightly, and that kind of got us hooked,” Lamb tells Mental Floss. “We started [to look] across salamander diversity, [and asked ourselves], ‘OK, how many species do we see within salamanders that biofluoresce?’ When we started to notice, ‘hey, it’s actually a lot of them!’, the question became, ‘can frogs do it?’ Then we looked at a relative of frogs, the caecelians—‘do they do it?’ And it seemed like biofluorescence in some form or fashion is present in all of these lineages.”

Biofluorescent salamander
A biofluorescent Eastern tiger salamander
Jennifer Y. Lamb and Matthew P. Davis

The various amphibians fluoresced in unique patterns depending on their skin’s coloration and markings as seen under normal white light. Some gleamed in blotches, others in stripes. A few animals' bones glowed. Lamb was surprised to see that salamanders’ bellies, which were usually red or orange under white light, glowed brighter than their backs after exposure to blue light.

“A lot of these newts have evolved what we call aposematic coloration, or warning colors. When they’re threatened by a predator, they’ll basically contort their bodies to show off their bellies as a warning,” Lamb says. “So it begs the question, if these bellies are also biofluorescent, then maybe some of their predators can visualize biofluorescence.”

The researchers intend their study to be a roadmap for further study into the fascinating ability. “Now that we know that this phenomenon exists across amphibians, there’s all kinds of interesting applications that future researchers may head towards,” Davis tells Mental Floss. For example, no one yet knows what kind of mechanisms allow amphibians to biofluoresce: In some groups it might be a color-based molecule or compound; in others, maybe something in their mucus.

Biofluorescent frog
A Cranwell's frog glows under blue light.
Jennifer Y. Lamb and Matthew P. Davis

Scientists also don’t know exactly how different amphibians might visualize their own biofluorescence. Salamanders, frogs, and caecelians have rod cells in their eyes that are sensitive to green light, suggesting that they may have evolved green biofluorescence and the ability to see it at the same time, though further research is needed on that front.

“We have to be careful about not falling into the trap of only perceiving the world through our own eyes,” Lamb says. “Human vision is set to a particular set of wavelengths, and that’s not the case across all animal diversity. And that may not be the case in terms of these amphibians.”

Biofluorescent salamander
A biofluorescent three-lined salamander
Jennifer Y. Lamb and Matthew P. Davis

Finally, researchers are debating what purpose biofluorescence serves. In other animals, scientists have suggested it could play a role in communication, camouflage, or choosing a mate. Amphibians might use biofluorescence to locate each other in dense leaf litter.

“We’re hoping this study stimulates researchers to start looking at biofluorescence more broadly across the various different kinds of amphibian lineages that they may work on, so we can fill in the gaps in knowledge,” Davis says.

“There’s still a lot to learn about animal groups that we think we know,” he adds. “There’s still lots of interesting things out there to find that can help us rethink their life history and biology, and that may point us in new exploratory directions.”

SECTIONS

arrow
LIVE SMARTER