關於左撇子你所不知道的事
With just 10% of the population being left-handed, it can be easy for everyone else to forget we're living in a right-handed world. But aside from making it tough to cut a straight line with a pair of scissors designed for righties, being a southpaw can also have some subtle effects on our physical and mental health.
由於左撇子在人口中比例僅爲10%，所以人們很容易忽略這樣一個事實，即自己正生活在一個左撇子的世界。除了能夠輕易地將自己同一般人區分開來之外，左撇子的習慣對個人的身體和心理健康還有着微妙的影響。The brains and bodies of lefties may operate differently than those of right-handed people (and in mixed-handed people, who may have different dominant hands for different tasks). "Handedness seems to be determined very early on in fetal development, when a lot of other things about your future are being determined as well," says Ronald Yeo, PhD, professor of psychology at the University of Texas-Austin. Here's a look at some of the most common facts about being left-handed, and what it might really mean for your health.
習慣用右手的人，其大腦和身體的運轉方式可能和左撇子有所不同 （對雙撇子來說，不同任務中他們會習慣用不同的手。）“人的許多特點在胎兒時期就已經形成了，偏手性似乎也不例外，”德克薩斯州大學奧斯汀分校的心理學教授、博士羅納德楊說。下面我們會探討有關左撇子的一些常識以及左撇子對健康的影響。
It's not just genetics
左撇子不一定都是遺傳因素導致的。
Scientists aren't exactly sure why some people are left-handed, but they know that genes are responsible about 25% of the time, says Yeo. Left-handedness does tend to run in families, he says, "but noticeably less than other inherited traits, like height or intelligence."
科學家們並不確定爲什麼有些人是左撇子，但是他們確信，左撇子的遺傳因素佔到25%。“左撇子的確會在家族內部遺傳，但與體重和智力等其他遺傳特性相比，其遺傳機率卻要小很多。”羅納德楊教授說。It's linked to stress in pregnancy
左撇子與懷孕期間的壓力有關。In one British study, the fetuses of super-stressed pregnant women were more likely to touch their faces more with their left hands than their right. This could be the first signs of a left-handed child, say the researchers. Other evidence supports that theory. In one 2008 Swedish study of moms and their 5-year-old children, women who were depressed or stressed during their pregnancies were more likely to have mixed- or left-handed kids. In other studies, babies with low birth weight, or born to older mothers, were more likely to be lefties as well.
英國一項研究顯示，壓力較大的孕婦生出的孩子 更傾向於用左手摸臉。這可能是左撇子在嬰幼兒時期的第一個徵兆。而其他研究結果也證實了這一結論。2008年，瑞典的一項研究顯示，孕期較爲壓抑或壓力較大的婦女，她們的寶寶成爲左撇子或雙撇子的可能性更大。其他研究還顯示，出生時體重較低的嬰兒或高齡產婦生產的嬰兒成爲左撇子的機率更大。
