您从决心开始假期。您发誓会避开饼干，并将鸡尾酒限制在一个顶部，顶部两个。一开始你做到了。但是，每次派对的派对，饼干托盘和开放式酒吧的呼唤变得更大，直到您终于陷入困境。到新年到来时，糖果（以烘焙食品或含糖解放的形式）已成为您日常饮食的一部分。几磅之后，您不知道：我是怎么做到这一点的？事实证明，虚弱的意志力并不是完全归咎于责备。
Ina new paperpublished in Cognitive Neuroscience, researchers set out to see how the大脑的自我控制和奖励中心square offwhen they spot a food signal and how the pathway between those centers might affect your ability to abstain from temptation. To investigate this, they examined the white matter connections inside the minds of 36 women, ages 18–23, with a history of diet failures. They also measured their total body-fat percentages, which ranged between 16.6–38.2%.
THE STUDY
At the start of the experiment, subjects were asked to watch a seven-minute video about Canadian bighorn sheep while trying to ignore words on screen that aimed to distract them. The point of the sheep flick was to get people to let their guard down so their reactions were more natural. Once the ladies loosened up a bit, they were ready for the real examination to begin.
Each woman was hooked up to a functional MRI machine and asked to look at a series of 270 pictures. Two-thirds of the photos were images of people or nature. The other 90 were shots of appetizing food. For every photo that appeared, the women were asked to mark whether it showed something indoors or outdoors. Their answers, however, weren’t what interested researchers, who were really out to monitor the fMRI recordings of their brain activity.
The researchers were primarily concerned with two areas in the brain: the orbitofrontal cortex, which is considered the reward region, and the inferior frontal gyrus, which is associated with self-control and decision making. Images of tantalizing food elicited a greater response from the reward region than the pictures of nature or people. That much was expected. Try as we might to appreciate beautiful scenery, our brains are hardwired to see edible delights as more rewarding. That makes sense on an evolutionary level — a breathtaking sunset won’t keep you alive when you’re starving.
THE AHA! MOMENT
从字面上看，虽然这种反馈是不费吹灰之力的，但吸引科学家的东西是受试者来自大脑控制区域的反应。IFG还显示出增强的活性。
“One interpretation is that dieters are super aware of food cues in every instance,” study author Pin-Hao Andy Chen, a doctoral candidate in cognitive neuroscience at Dartmouth College, explained in an email. “They have to constantly regulate (inhibit and monitor) their desires to appetitive food cues in daily life.”
因此，从本质上讲，在慢性节食者的大脑中，食物同时引起了两种反应。他们思想的回报是说：“哦，好！吃！”同时，控制部分是说“不！不要做！”如果这听起来很累 - 就像大脑在与自己争论一样，那是因为它是。而且“不做！”有多长时间的限制。部分可以赢。自我调节是有限的资源。
“When [dieters] keep doing this, they become more vulnerable to lose control because their regulation resource has been drained,” Chen says.
为什么白色重要
在考试之后的分析中，研究人员做出了另一个有趣的发现。连接奖励区域（OFC）和控制区域（IFG）的白质途径较高的人体脂肪百分比较弱。较弱的白质使这两个部分彼此之间的交流能力降低，科学家说，这也可以在自我控制失败中发挥作用。
“With an inefficient communication between the executive control and reward regions, individuals with reduced [white matter] integrity may have difficulty in overriding rewarding temptations, leading to a greater chance of becoming obese,” the paper states.
这项研究中很明显的是，当奖励和自我控制之间的白质连接较弱时，该人就会更重。不清楚的是为什么会发生这种情况。陈推测所有节食失败可能会削弱这一路径。但是，从一开始，连接也很可能弱，并可能导致自我控制中的那些失误。陈确认在科学知道答案之前需要更多的研究。
同时，有GOOD新闻，您可以随身携带下一个重度派对，例如Super Bowl Sunday。一些新兴科学表明您可以通过训练。其他研究还表明，您可以通过practice。The takeaway might be that willpower, like any form of strength, must be developed incrementally.
