PLoS ONE：婴儿也有“纠结之心”

很多婴儿在出生半年之后开始变得认生，研究人员之前一直未弄清这一机制。

日前，日本东京大学和京都大学的一个联合研究小组发现，婴儿认生不光是因为对陌生人感到恐惧，还有虽然感兴趣、想靠近但是又感到害怕的“纠结”心情在作怪。相关研究论文已经刊登在了PLoS ONE上。

在这项研究中，科学家以 57 名 7 至 12 个月大的婴儿为对象，对其母亲进行问卷调查，调查婴儿的性情。

调查结果显示，虽然认生非常严重的婴儿看起来更害怕陌生人，但另一方面，与认生程度中等的婴儿相比，他们想靠近对方的心情也更加强烈。研究小组认为，这表明婴儿同时拥有“想靠近”和“想离开”的相反心情。

此外，研究小组在调查婴儿的视线时发现，越是认生的婴儿，越愿意注视陌生人的眼睛，且更愿意长时间观看对方的侧脸，这表明婴儿已经出现了在相反情绪间动摇的纠结心情。

Shyness in Early Infancy: Approach-Avoidance Conflicts in Temperament and Hypersensitivity to Eyes during Initial Gazes to Faces
Abstract
‘Infant shyness’, in which infants react shyly to adult strangers, presents during the third quarter of the first year. Researchers claim that shy children over the age of three years are experiencing approach-avoidance conflicts. Counter-intuitively, shy children do not avoid the eyes when scanning faces; rather, they spend more time looking at the eye region than non-shy children do. It is currently unknown whether young infants show this conflicted shyness and its corresponding characteristic pattern of face scanning. Here, using infant behavioral questionnaires and an eye-tracking system, we found that highly shy infants had high scores for both approach and fear temperaments (i.e., approach-avoidance conflict) and that they showed longer dwell times in the eye regions than less shy infants during their initial fixations to facial stimuli. This initial hypersensitivity to the eyes was independent of whether the viewed faces were of their mothers or strangers. Moreover, highly shy infants preferred strangers with an averted gaze and face to strangers with a directed gaze and face. This initial scanning of the eye region and the overall preference for averted gaze faces were not explained solely by the infants’ age or temperament (i.e., approach or fear). We suggest that infant shyness involves a conflict in temperament between the desire to approach and the fear of strangers, and this conflict is the psychological mechanism underlying infants’ characteristic behavior in face scanning.