Ninety-five percent of adult Americans sleep seven to eight hours a night. The rest seem to need more than nine hours, or get along nicely on less【1】six. What distinguishes the long and short sleepers【2】the majority? To get some answers psychologist Ernest Hermann in Boston and New York papers for long and【3】sleepers to engage in an eight-night 'sleep in' at Boston State Hospital's Sleep and Dream laboratory. His findings indicate that such people differ【4】ordinary sleepers and each other not【5】much physically as psychologically. Testing showed significant psycho logical【6】between long and short sleepers. The shorts【7】to be emotionally stable. Their entire life-style【8】keeping busy and avoiding psychologist problem【9】than facing them. They were also awakened seldom during the night and rose in the【10】refreshed and ready to go. (31)