爲什麼飢餓感相比口渴、焦慮和害怕更能刺激人?

Hunger is more powerful than thirst, fear or anxiety, new research suggests.

最新研究表明，飢餓對人的影響比口渴、恐懼或者是焦慮都要大。

Scientists at the National Institutes of Health found lab mice would be willing to put themselves in danger or cut themselves off socially if it meant they could eat.

美國國立衛生研究院的科學家們發現，如果實驗室的老鼠在糧食充足的情況下，它們甚至願意將自己置身於危險之中，或者切斷自己與社會的聯繫。

The mice also picked food over water in every scenario.

在不同的實驗環境下，老鼠們相對於飲水更傾向於選擇食物。

The findings have been hailed as a crucial step towards our understanding of eating disorders and how to control food cravings.

這項發現已經被視爲人們瞭解飲食失調及如何控制對食物的渴望的至關重要的一步。

It is the first research that pits different cravings against each other, looking at how hunger affects us in a more naturalistic setting.

研究人員首次在相互競爭的狀態下對人類不同的慾望進行研究，並觀察飢餓如何在自然環境中對我們產生影響。

Previous studies have isolated each craving - hunger, thirst, fear - to work out how the brain triggers such instincts.

先前的研究中，人們將不同的慾望進行分開，例如飢餓、口渴和恐懼，同時觀察大腦如何觸發人類的這種本能。

But now experts in diabetes and obesity are looking at how powerful each craving is, in relation to our other survival instincts.

但現在糖尿病和肥胖症的相關專家研究的是幾種不同生存本能之間的關係，並瞭解單個生存本能對人體產生的影響。

The study, carried out by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), put mice in different scenarios where they would have to choose between cravings.

該研究由美國國家糖尿病、消化及腎臟疾病研究中心(NIDDK)負責承擔，研究人員將實驗小鼠放在不同的實驗條件下，並讓其在不同的生存本能之間做出選擇。

To make them hungry, the scientists did one of two things: deprived the mice of food for 24 hours or activated neurons that are known to cause hunger.

爲了讓實驗小鼠處於飢餓狀態，科學家們會讓小鼠處於飢餓狀態24小時，或者激活能夠產生飢餓感的神經元中心。

A similar process was performed to make them thirsty. To make them scared they would put them in a large space which smelled like foxes.

讓它們產生口渴感的方式與讓其產生飢餓感的方式相同。至於恐懼感，爲了讓小鼠產生恐懼會將其放置在聞起來有點像狐狸味道的環境中。

In one set of experiments, mice that were both thirsty and hungry consumed more food at the expense of drinking water. That, however, was the least surprising result.

實驗中，又渴又餓的小鼠們在同樣的條件下相比飲水消耗了更多的食物。然而，這樣的結果卻是讓人十分驚訝的。

To their astonishment, hungry mice placed in a scary situation would overcome their fear and venture ahead if they knew there was food in the danger zone.

讓實驗人員驚訝的是，將飢餓的小鼠們放置在令它們感到害怕的環境中，如果它們知道這裏有食物，則會選擇剋制自己的恐懼。

By contrast, sated mice preferred to stay in 'safe' corner zones or in a non-scented chamber rather than venture out into the more risky locations.

相比之下，吃飽的小鼠們則會選擇待在相對“安全”的角落，而不會冒着風險去探索其它區域。

Hunger also drove mice to cut themselves off socially. Hungry mice preferred to spend time in a chamber with food rather than a different chamber containing another mouse.

解餓感也會趨勢小鼠切斷自己於社會間的聯繫。處於飢餓狀態的小鼠寧願選擇自己一個人待在有食物的屋子裏，也不去另外一間屋子跟一羣小鼠混在一起。

Mice that were lonely but not hungry strongly preferred the company of another mouse to a chamber baited with food.

具有強烈孤獨感但是還不是很餓的小鼠，則會選擇尋找自己同伴，而不再獨自躲在有食物的屋子裏。

'We interpret this as a unique ability of hunger-tuned neurons to anticipate the benefits of searching for food, and then alter behavior accordingly,' lead author Dr Michael Krashes said.

研究項目負責人邁克爾·克拉希斯博士表示；“我們認爲獨特的飢餓調節神經元事先預測到食物的作用，並因此改變了生物體的行爲模式。”

'Evolutionarily speaking, animals that consistently picked the right motivations over others have survived while other animals have not.'

“從進化論的角度來說，能夠活下的動物們都是做出來正確的選擇，而其它的動物我們就可想而知了。”