chuanzhan@sina.com问:我的孩子4岁多,每天晚上10点左右上床睡觉,转天早上不到5点就醒。请问,孩子的睡眠时间少是由什么原因造成的?答:如果长期以来一直如此,而且孩子的日常生活和精神状态并无异常,就说明他每天的睡眠总量是足够的。孩子的睡眠受许多因素的影响,比如年龄、精神因素、气质特点、疾病、睡眠习惯、环境温度、噪音、光线、家庭 chuanzhan@sina.com Q: My child is 4 years old and goes to bed around 10 pm every day. She woke up less than 5 o’clock in the morning. May I ask, what is the reason why the child’s sleep time is low? A: If it has been so for a long time, and the child’s daily life and mental state are normal, it shows that his daily total amount of sleep is sufficient. Children’s sleep is affected by many factors, such as age, mental factors, temperament, illness, sleep habits, ambient temperature, noise, light, family