Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
Infant Behav Dev. 2009 Dec;32(4):416-21. doi: 10.1016/j.infbeh.2009.07.005. Epub 2009 Aug 8.
Five infants were observed longitudinally. In over 30 h of observations, seven spontaneous smiles and one spontaneous laugh were found. All smiles were observed in infants between the ages of 10 and 15 months. These data indicate that spontaneous smiles do not disappear at 2 months of age and they still exist at over 15 months. This disproves some emotional expression theories, where spontaneous smiles are considered to be precursor to and replaced by social smiles. Our data suggest that those theories must be revised and provide new perspectives on this field of studies.
对五名婴儿进行了纵向观察。在超过 30 小时的观察中，发现了 7 次自发性微笑和 1 次自发性大笑。所有的微笑都发生在 10 至 15 个月大的婴儿身上。这些数据表明，自发性微笑不会在 2 个月大时消失，并且在 15 个月以上仍然存在。这反驳了一些情感表达理论，即自发性微笑被认为是社会微笑的前身和替代品。我们的数据表明，这些理论必须加以修正，并为这一研究领域提供新的视角。
