|
外语专家
 
- 积分
- 1072
|
One of the strangest findings to emerge from the world of obesity science lately is that people who sleep less tend to weigh more. But until recently, we have been stifling our yawns and scratching our heads about why: Does lack of sleep alter our biology? Or does it affect our eating behavior? Now two brain-imaging reports suggest the answer is both.
在对于肥胖的科学研究中有一项十分诡异的发现，那就是睡觉少的人往往较胖。但是直到不久之前人们还百思不得其解：是因为睡眠不足改变了我们的生物代谢？还是改变了人们的饮食习惯？最近的两项大脑成像研究表明两者皆有可能。
The first study, published in March in the Journal of Clinical Endocrinology & Metabolism, looked at the effects of one night of no sleep. The second, published in April in the American Journal of Clinical Nutrition, tested the impact of nearly a week of more commonly experienced levels of sleep deprivation (four hours of sleep for six nights).
第一项研究刊登于三月的《临床内分泌与代谢杂志》，探究了一整夜不睡觉对人的影响。第二项研究刊登于四月的《美国临床营养学杂志》，试验了近一周睡眠不足（连续六日每日只睡四小时，相比整夜不睡，在人群中更为常见）带来的影响。
Both studies used functional MRI to measure brain activation as their subjects viewed food pictures—analogous to being bombarded with a stream of McMuffin ads after a long night of working (or partying). Each study discovered that sleep loss caused areas within a key motivation network, including the striatum and anterior cingulate cortex, to go into overdrive at the mere sight of food. The same circuit perks up when addicts view images of their substance of choice.
两项研究均使用功能磁共振成像来探测受试者观看食物图片时的大脑活动--此情景类似于结束了一整夜的工作或者派对之后被一堆麦满分三明治的广告狂轰滥炸。两项研究都发现，睡眠不足会导致大脑中含有重要的动机回路的部分，包括终脑皮层和前扣带皮层，在见到食物时变得过度兴奋。这一回路同样会在人见到使其上瘾的物品 （比如酒鬼见到酒）时变得兴奋。
“Calories are energy, and your brain subconsciously knows they will wake you up,” says Marie-Pierre St-Onge of Columbia University, lead investigator of the April study. She likens the superresponsive sleep-poor brain to that of someone who has lost weight on a drastic diet—devouring the first snack you can get your hands on is a “no-brainer.”
“卡路里代表着能量，而你的大脑潜意识里觉得补充点卡路里能使你变得清醒”，第二项研究的领导者，哥伦比亚大学的玛丽-皮埃尔-圣安表示。她把一个人在睡眠不足后大脑对食物的反应比作一个减肥的人对食物的反应--当惨烈的节食结束之后，你会不假思索地抓起你能拿到的第一样零食往嘴里送。
Scientists do not fully understand how sleep loss affects the machinery of neural motivation. Past studies have established that the stress of sleep deprivation puts the autonomic nervous system on alert, leading to increases in the hunger hormone ghrelin and decreases in the satiety hormone leptin. These changes may be detected by the brain's motivation circuits—which respond by keeping an eye out for doughnuts.
科学家们尚未完全了解睡眠不足影响神经动机的机理。 过去的研究表明睡眠不足产生的压力使自主神经系统高度警觉，从而使生长素释放激素（使人产生饥饿感）分泌增加，而瘦素（使人产生饱足感）减少。这些激素的变化被大脑动机回路探测到，随之人变得更贪吃，比如总想来个甜甜圈什么的。
Christian Benedict, a neuroscientist at Uppsala University in Sweden who co-led the March study, is also exploring whether sleep restriction could interfere with the way our brain perceives the taste of high-calorie foods.
第一项研究的合作者之一，瑞典乌普萨拉大学神经生物学家克里斯蒂安·班尼迪克，同时也在研究睡眠不足是否能影响大脑对于高热量食物口味的感知。
Whatever the underlying biology, it seems that skimping on sleep could well make us hungry as well as irritable. So if you're watching your waistline and feeling snoozy, it's probably wise to avoid the breakfast buffet until you get a chance to nap.
尽管还不清楚这一现象的生物学机制，但是看来睡眠不足会使我们变得饥饿和烦躁。如果你想保持身材，可是总是困意连连，那么在享受一顿自助早餐之前还是打个小盹吧！ |
本帖子中包含更多资源
您需要 登录 才可以下载或查看，没有帐号？立即注册
x
|
发表于 2012-6-25 10:11:34
收藏