研究:适当嘈杂声有助睡眠

　　Forget counting sheep -- Britons now prefer listening to lions roaring and monkeys calling to help them nod off, according to a new survey。

　　The poll, which questioned 2,000 adults about falling asleep at night, found that birds twittering and rainforest noises are the most soothing sounds for one in five people at bedtime, with fewer than one in 10 relying on counting sheep to send them into slumber。

　　"These noises can stop intrusive thoughts," John Shneerson, President of the British Sleep Society and consultant at Papworth Sleep Center in Britain。

　　"A repetitive noise has an occasional rhythm change, works by distracting you. The sound can't be too boring but should not be so stimulating that you actively think about it -- it has to be something in the middle," Shneerson said。

　　While the relaxing properties of natural sound may not come as a surprise, noises generally considered to be irritating, such as passing traffic and ticking clocks can also be soporific, according to the survey。

　　The study was commissioned by Chessington World of Adventure Resort, the British theme park。