科学家揭秘为何新年决心难坚持

Uh-oh, the new year's just begun and already you're finding it hard to keep those resolutions to junk the junk food, get off the couch or kick smoking. There's a biological reason a lot of our bad habits are so hard to break – they get wired into our brains.

That's not an excuse to give up. Understanding how unhealthy behaviors become ingrained has scientists learning some tricks that may help good habits replace the bad.

"Why are bad habits stronger? You're fighting against the power of an immediate reward," says Dr. Nora Volkow, director of the National Institute on Drug Abuse and an authority on the brain's pleasure pathway.

"We all as creatures are hard-wired that way, to give greater value to an immediate reward as opposed to something that's delayed," Volkow says.

Just how that bit of happiness turns into a habit involves a pleasure-sensing chemical named dopamine. It conditions the brain to want that reward again and again – reinforcing the connection each time – especially when it gets the right cue from your environment.

People tend to overestimate their ability to resist temptations around them, thus undermining attempts to shed bad habits, says experimental psychologist Loran Nordgren, an assistant professor at Northwestern University's Kellogg School of Management.

Even scientists who recognize it can fall prey.

"I don't like popcorn. But every time I go to the cinema, I have to eat it," Volkow says. "It's fascinating."

A movement to pay people for behavior changes may exploit that connection, as some companies offer employees outright payments or insurance rebates for adopting better habits.

However paying for behavior plays out, researchers say there are some steps that may help counter your brain's hold on bad habits:

Repeat, repeat, repeat the new behavior – the same routine at the same time of day. Resolved to exercise? Doing it at the same time of the morning, rather than fitting it in haphazardly, makes the striatum recognize the habit so eventually, "if you don't do it, you feel awful," says Volkow the neuroscientist, who's also a passionate runner.

Exercise itself raises dopamine levels, so eventually your brain will get a feel-good hit even if your muscles protest.

Reward yourself with something you really desire, Volkow stresses. You exercised all week? Stuck to your diet? Buy a book, a great pair of jeans, or try a fancy restaurant - safer perhaps than a box of cookies because the price inhibits the quantity.

噢喔，新的一年才刚刚开始，你就发现很难坚持“告别垃圾食品、远离沙发、戒烟”这些新年决心了吧？我们很难改掉坏习惯是由于生物学的原因——这些坏习惯根植于我们的大脑中。

这并不是让人放弃新年决心的借口。了解不健康的习惯怎样变得根深蒂固可以启发科学家研究出一些让好习惯代替坏习惯的“技巧”。

诺拉．沃尔科夫博士说：“为什么坏习惯更加顽固？因为它能带来即时的犒赏，而这种即时犒赏的力量很强大。”沃尔科夫博士是美国国家药物滥用研究所主任，同时也是大脑快乐通道方面的权威。

沃尔科夫博士说，“我们的这种天性决定了我们会更看重眼前的好处，而不是迟来的好处。”

那么这一点快乐的感觉是怎样转化为一种习惯的呢？这与一种感知快乐的化学物质多巴胺有关。多巴胺使大脑不断期望得到这种犒赏，从而不断加强快乐感与这种行为之间的联系，特别是当它能从周围环境中得到正确的暗示时。

西北大学凯洛格管理学院副教授、实验心理学家罗兰．诺德格伦说，人们往往高估自己抵抗身边诱惑的能力，这使他们为摆脱坏习惯而做出的努力毁于一旦。

即使是能意识到这一点的科学家，也难以幸免。

沃尔科夫说：“我不喜欢吃爆米花，但每次去电影院我都会吃。它让我很难抗拒。”

一项“为行为变化买单”的运动可能会对这种联系加以利用，在这项运动中，一些公司给雇员提供“即时报酬”或是“保险回扣”，以激励他们形成更好的习惯。

不管这项运动结果如何，研究人员说我们的确可以采取某些行动来对抗坏习惯对大脑的吸引力。

那就是，重复，重复，再重复你的新行为，使之成为每天固定时间的例行活动。下决心锻炼？那就每天早上固定时间锻炼，而不要随意找时间，这样会使大脑纹状体最终接受这个新习惯。神经学家沃尔科夫也是一个热爱跑步的人，他说：“如果你哪天没锻炼，就会感觉很糟糕。”

运动本身能提升多巴胺的水平，这样尽管运动结束后你的肌肉感觉酸痛，但是你的大脑还是会感觉良好。

沃尔科夫强调说，要奖励自己一点你真正想要的东西。你坚持锻炼了一整周？严格遵循了你的节食食谱？那给你自己买本书，买一条漂亮的牛仔裤，或者去一家高档的餐馆吧！这应该会比买一盒曲奇饼要安全，毕竟，餐厅的价格会提醒你别吃那么多东西。

Vocabulary:

dopamine: 多巴胺

outright: immediately（立刻的，即时的）

play out: 结束

striatum: 纹状体