People who spend more pre-bedtime hours using the Internet or watching television are more likely to report that they don't get enough sleep, even though they sleep almost as long as people who spend fewer pre-bedtime hours in front of a computer or television screen, survey findings show. 

    "While many people use electronic media, such as the Internet, it should be noted that the longer media use before sleep can trigger (self-perceived) insufficient sleep," lead researcher Dr Nakamori Suganuma, of Osaka University, Japan, told the reporter. 

    He and colleagues obtained data on self-perceived sleep problems and the use of electronic media prior to bedtime from a total of 5,875 Japanese respondents in two separate Internet-based surveys. Their findings are published in the journal Sleep and Biological Rhythms. 

    Nearly half of the respondents associated their lack of sleep with electronic media use before bedtime. Those reporting longer electronic media use were also more likely to report insufficient sleep. 

    Overall, 29 percent of light users (less than 1.5 hours) listed electronic media use as a possible cause of their insufficient sleep. By comparison, 40 percent of medium users (1.5 to 3 hours) and 54 percent of heavy users (more than 3 hours) said the same. 

    However, longer Internet and television use before bedtime did not correlate with less actual sleep. 

    While heavy users averaged about 3 more hours in front of computer or television screens than light users, the heavy users averaged only about 12 minutes less pre-workday sleep time than light users. 

    Notably, Suganuma said, "Internet use affected self-perceived insufficient sleep more than TV watching ... not only in younger Internet users but also in middle-aged or aged Internet users." 

    Up to 38 percent of the respondents listed accessing the Internet far into the night as a possible cause for their sleep disturbance, while about 25 percent said watching television far into the night caused their sleep problems. 

    The findings suggest that while heavy computer and television use before bedtime has a small effect on sleep duration, it may have a more significant effect on "sleep demand and sleep quality," Suganuma notes. 

    调查显示，睡前长时间上网或看电视的人称自己睡眠不足的几率更大，即使他们的睡眠时间与在睡前上网或看电视时间较短的人一样多。 

    首席研究员、日本大阪大学的菅沼中森在接受记者采访时说：“如今，很多人使用互联网等电子媒体，但应该注意的是，睡前长时间使用会引起（自我感觉的）睡眠不足。” 

    他与其他同事通过两个在线调查，收集了5875名日本受访者有关自我感觉的睡眠问题及睡前使用电子媒体的数据。调查结果在《睡眠与生物节律》期刊上发表。 

    近一半的受访者认为睡眠不足与睡前使用电子媒体有关。称长时间使用电子媒体的人说自己睡眠不足的几率更大。 

    总体来看，有29%的轻度使用者（少于1.5小时）将使用电子媒体列为可能导致睡眠不足的原因。而有40%的中度使用者（1.5至3小时）和54%的重度使用者（3小时以上）持相同看法。 

    然而，睡前长时间上网或看电视时间与实际睡眠较少并不相关。 

    重度使用者上网或看电视的时间比轻度使用者平均多3个多小时，但他们工作日期间的睡眠时间平均仅比轻度使用者少12分钟。 

    菅沼特别指出，“无论是年轻网民还是中老年网民，上网比看电视更会让他们感觉睡眠不足。” 

    多达38%的受访者认为上网至深夜可能是睡眠不足的一个原因，25%的人说看电视看到很晚是出现睡眠问题的原因。 

    调查表明，睡前过度上网或看电视对睡眠时间没什么太大影响，菅沼说，这可能会对“睡眠需求和睡眠质量”产生更为显著的影响。 

    Vocabulary:

    pre-bedtime :睡前