研究顯示 睡眠不足會讓人易怒
Losing just two hours of sleep a night makes people angrier, research reveals.
研究顯示，每晚少睡兩個小時會讓人更易怒。
The study is among the first to prove a direct link with lack of shuteye, experts say.
專家稱，這是首個證明生氣和睡眠不足有直接聯繫的研究。
Previous research shows sleep loss increases negative emotions, such as anxiety and sadness, and decreases positive emotions, including happiness and enthusiasm.
之前的研究表明，睡眠不足會增加消極情緒，如焦慮和悲傷，減少積極情緒，包括幸福和熱情。
But researchers at Iowa State University found losing sleep raised anger directly -- not just as a result of feeling more negative. Their findings were published in the Journal of Experimental Psychology.
但愛荷華州立大學的研究人員發現，睡眠不足會直接引發憤怒，而不僅僅是感覺更消極。他們的研究結果發表在《實驗心理學雜誌》上。
Participants were split into two groups. One kept to their normal sleep routine while the other had theirs cut by two to four hours each night for two nights.
參與實驗者被分成兩組。一組保持正常的睡眠習慣，另一組連續兩晚每晚減少兩到四個小時的睡眠時間。
The first group had almost seven hours of sleep a night, while the restricted group got about four and a half hours.
第一組每晚差不多睡7個小時，而限制睡眠組每晚睡大約4個半小時。
The difference was designed to reflect what people regularly experience in everyday life.
設計這種差異是爲了反映人們在日常生活中經常經歷的情況。
Both groups were then asked to rate different products while listening to irritating noise. The researchers said this was meant to create uncomfortable conditions and provoke feelings of anger.
兩組參與者被要求在聽惱人的噪音的同時給不同產品評分。研究人員稱，這樣做是爲了營造不舒服的環境，激起憤怒的情緒。
study leader professor Zlatan Krizan said: "In general, anger was substantially higher for those who were sleep restricted."
研究負責人茲拉坦·克里薩教授表示：“總的來說，那些睡眠不足的人的憤怒情緒要高得多。”
"We manipulated how annoying the noise was during the task and, as expected, people reported more anger when the noise was more unpleasant. When sleep was restricted, people reported even more anger, regardless of the noise."
“我們對實驗過程中噪音的干擾程度進行了調控，結果不出所料，當噪音更惱人時，人們會表現得更憤怒。當睡眠不足時，不管是否有噪音，人們會表現得更憤怒。”
