左利手的发生率通常约为10%,于脑损伤特别是损伤发生于优势建立之前,其发生率较高。Satz假设如果偏利半球优势遭受损伤,则偏利将发生改变。由于出生时超低体重(ELBW,体重低于1000g)儿童中左利手较多,为探讨左利手的原因,作者对1979～1981年在新生儿加强监护病房护理过的115例儿童(主要组)进行随访调查,其中76%为正常新生儿,18例为ELBW儿。这些儿童于4岁时按记分对其手偏利进行评定。记分方法一是根据其母亲叙述,高度右利手记+2分,高度左利手记-2分,轻度左、右利手分别记-1,+2分,无偏利记0分。二是根据儿童取物及锤击试验,如为左利手记-1 The rate of left-handedness is usually about 10%, and the incidence is high before brain damage, especially damage, occurs when advantages are established. Satz assumes that if the hemispheric advantage is compromised, the bias will change. Due to the fact that there are more left-handed individuals in children born with ultra-low birth weight (ELBW, less than 1000g), in order to explore the reasons for left-handedness, the authors evaluated 115 children who were treated in neonatal Intensive Care Units from 1979 to 1981 Group) were followed up, of which 76% of normal newborns, 18 cases of ELBW children. At the age of 4, these children assessed their hand by points. Scoring method one is based on the description of his mother, a high degree of right-handed notes +2 points, a high degree of left-handed notes -2 points, mild left and right hand were recorded -1, +2 points, no bias score 0 points. The second is based on childrens fetches and hammer tests, such as left-handed notes -1