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更新時間:2019/4/25 20:16:14 來源:紐約時報中文網 作者:佚名

Putting Down Your Phone May Help You Live Longer

If you’re like many people, you may have decided that you want to spend less time staring at your phone.


It’s a good idea: an increasing body of evidence suggests that the time we spend on our smartphones is interfering with our sleep, self-esteem, relationships, memory, attention spans, creativity, productivity and problem-solving and decision-making skills.


But there is another reason for us to rethink our relationships with our devices. By chronically raising levels of cortisol, the body’s main stress hormone, our phones may be threatening our health and shortening our lives.


Until now, most discussions of phones’ biochemical effects have focused on dopamine, a brain chemical that helps us form habits — and addictions. Like slot machines, smartphones and apps are explicitly designed to trigger dopamine’s release, with the goal of making our devices difficult to put down.


This manipulation of our dopamine systems is why many experts believe that we are developing behavioral addictions to our phones. But our phones’ effects on cortisol are potentially even more alarming.


Cortisol is our primary fight-or-flight hormone. Its release triggers physiological changes, such as spikes in blood pressure, heart rate and blood sugar, that help us react to and survive acute physical threats.


These effects can be lifesaving if you are actually in physical danger — like, say, you’re being charged by a bull. But our bodies also release cortisol in response to emotionalemotional stressors where an increased heart rate isn’t going to do much good, such as checking your phone to find an angry email from your boss.


4 Hours a Day


If they happened only occasionally, phone-induced cortisol spikes might not matter. But the average American spends four hours a day staring at their smartphone and keeps it within arm’s reach nearly all the time, according to a tracking app called Moment. The result, as Google has noted in a report, is that “mobile devices loaded with social media, email and news apps” create “a constant sense of obligation, generating unintended personal stress.”


“Your cortisol levels are elevated when your phone is in sight or nearby, or when you hear it or even think you hear it,” says David Greenfield, professor of clinical psychiatry at the University of Connecticut School of Medicine and founder of the Center for Internet and Technology Addiction. “It’s a stress response, and it feels unpleasant, and the body’s natural response is to want to check the phone to make the stress go away.”

“當你的手機在你的視線範圍內或附近,又或者當你听到它,甚至認為你听到它時,你的皮質醇水平就會升高。”康涅狄格大學(University of Connecticut)醫學院的臨床精神病學教授、互聯網和科技成癮研究中心(Center for Internet and Technology Addiction)的創始人大衛•格林菲爾德(David Greenfield)說。“這是一種壓力反應,它讓人感到不舒服,而身體的自然反應是想要看看手機,讓這種壓力消失。”

But while doing so might soothe you for a second, it probably will make things worse in the long run. Any time you check your phone, you’re likely to find something else stressful waiting for you, leading to another spike in cortisol and another craving to check your phone to make your anxiety go away. This cycle, when continuously reinforced, leads to chronically elevated cortisol levels.


And chronically elevated cortisol levels have been tied to an increased risk of serious health problems, including depression, obesity, metabolic syndrome, Type 2 diabetes, fertility issues, high blood pressure, heart attack, dementia and stroke.


“Every chronic disease we know of is exacerbated by stress,” says Dr. Robert Lustig, emeritus professor in pediatric endocrinology at the University of California, San Francisco, and author of “The Hacking of the American Mind.” “And our phones are absolutely contributing to this.”

“我們所知的各種慢性病都會因壓力而惡化,”加州大學舊金山分校(University of California, San Francisco)兒科內分泌學榮休教授、《美國人心智的黑客》(The Hacking of the American Mind)一書作者羅伯特•拉斯蒂格(Robert Lustig)說。“而我們的手機無疑在加劇這一點。”

Smartphone Stress


In addition to its potential long-term health consequences, smartphone-induced stress affects us in more immediately life-threatening ways.


Elevated cortisol levels impair the prefrontal cortex, an area of the brain critical for decision-making and rational thought. “The prefrontal cortex is the brain’s Jiminy Cricket,” says Dr. Lustig. “It keeps us from doing stupid things.”

皮質醇水平的升高會損傷前額皮質,這一大腦區域對決策與理性思考至關重要。“前額皮質是大腦的小蟋蟀吉明尼(Jiminy Cricket,《木偶奇遇記》里的重要角色,以智慧、風趣和樂觀著稱。——譯注)”魯斯提說。“它能讓我們避免做蠢事。”

Impairment of the prefrontal cortex decreases self-control. When coupled with a powerful desire to allay our anxiety, this can lead us to do things that may be stress-relieving in the moment but are potentially fatal, such as texting while driving.


The effects of stress can be amplified even further if we are constantly worrying that something bad is about to happen, whether it’s a physical attack or an infuriating comment on social media. (In the case of phones, this state of hypervigilance sometimes manifests as “phantom vibrations,” in which people feel their phone vibrating in their pocket when their phone isn’t even there.)


“Everything that we do, everything we experience, can influence our physiology and change circuits in our brain in ways that make us more or less reactive to stress,” says Bruce McEwen, head of the Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology at The Rockefeller University.

“我們所做的每件事,所經歷的每件事,都會對我們的生理機能產生影響,並改變我們的腦回路,使我們對壓力的反應程度增強或減弱,”洛克菲勒大學(Rockefeller University)哈羅德和瑪格麗特•米利肯•哈奇神經內分泌學實驗室(Harold and Margaret Milliken Hatch Laboratory of Neuroendocrinology)主任布魯斯•麥克尤恩(Bruce McEwen)說。

Dr. McEwen also notes that our baseline cortisol levels ebb and flow in a regular 24-hour cycle that is thrown out of whack if we get less than seven to eight hours of sleep a night, which is all too easy to do if you’re in the habit of checking your phone before bed. This in turn leaves our bodies less resilient to stress and increases our risk of all the stress-related health conditions mentioned above.


Put this all together, and the hours we spend compulsively checking our phones may add up to much more than a waste of time.


Breaking the Cycle


The good news is that if we break this anxiety-driven cycle, we can reduce our cortisol levels, which in turn may both improve our short-term judgment and lower our risks for long-term stress-related health problems. Over time, says Dr. McEwen, it’s even possible to retrain our brains so that our stress responses are no longer on such a hair-trigger to begin with.


To make your phone less stressful, start by turning off all notifications except for the ones you actually want to receive.


Next, pay attention to how individual apps make you feel when you use them. Which do you check out of anxiety? Which leave you feeling stressed? Hide these apps in a folder off your home screen. Or, better yet, delete them for a few days and see how it feels.


Regular breaks can also be an effective way to rebalance your body’s chemistry and regain your sense of control. A 24-hour “digital Sabbath” can be surprisingly soothing (once the initial twitchiness subsides), but even just leaving your phone behind when you get lunch is a step in the right direction.


Also, try to notice what anxiety-induced phone cravings feel like in your brain and body — without immediately giving in to them. “If you practice noticing what is happening inside yourself, you will realize that you can choose how to respond,” says Jack Kornfield, a Buddhist teacher at the Spirit Rock Meditation Center in California. “We don’t have to be at the mercy of algorithms that are promoting the fear of missing out.”

此外,盡力去留意焦慮引起的玩手機的欲望在大腦和身體里的感受是怎樣的——而不是立即順應它們。“如果你去練習留意身體的內部過程,你會意識到你可以選擇如何作出回應,”加州靈石禪修中心(Spirit Rock Meditation Center)的佛教導師杰克•康菲爾德(Jack Kornfield)說。“我們沒必要讓自己被一些算法所牽制,它們會增強害怕錯過的心理。”

Unfortunately, it isn’t easy to create healthy boundaries with devices that are deliberately designed to discourage them. But by reducing our stress levels, doing so won’t just make us feel better day-to-day. It might actually lengthen our lives.