University of Miami, United States.
Infant Behav Dev. 2013 Dec;36(4):776-85. doi: 10.1016/j.infbeh.2012.11.009. Epub 2013 Oct 2.
In infants, eye constriction-the Duchenne marker-and mouth opening appear to index the intensity of both positive and negative facial expressions. We combined eye constriction and mouth opening that co-occurred with smiles and cry-faces (respectively, the prototypic expressions of infant joy and distress) to measure emotional expression intensity. Expression intensity and heart rate were measured throughout the face-to-face/still-face (FFSF) in a sample of infants with prenatal cocaine exposure who were at risk for developmental difficulties. Smiles declined and cry-faces increased in the still-face episode, but the distribution of eye constriction and mouth opening in smiles and cry-faces did not differ across episodes of the FFSF. As time elapsed in the still face episode potential indices of intensity increased, cry-faces were more likely to be accompanied by eye constriction and mouth opening. During cry-faces there were also moderately stable individual differences in the quantity of eye constriction and mouth opening. Infant heart rate was higher during cry-faces and lower during smiles, but did not vary with intensity of expression or by episode. In sum, infants express more intense negative affect as the still-face progresses, but do not show clear differences in expressive intensity between episodes of the FFSF.
在婴儿中，眼睛收缩（杜兴氏标志）和口张开似乎可以指示积极和消极面部表情的强度。我们结合了与微笑和哭脸（分别是婴儿喜悦和痛苦的典型表情）同时出现的眼睛收缩和口张开，以衡量情感表达的强度。在有产前可卡因暴露风险的发育困难的婴儿样本中，我们在面对面/静止面（FFSF）期间测量了表情强度和心率。在静止面孔的情节中，微笑减少，哭脸增加，但在 FFSF 的各个情节中，微笑和哭脸中的眼睛收缩和口张开的分布没有差异。随着静止面孔情节中时间的流逝，强度的潜在指标增加，哭脸更有可能伴随着眼睛收缩和口张开。在哭脸期间，眼睛收缩和口张开的数量也存在适度的个体差异。婴儿在哭脸时的心率较高，在微笑时较低，但不受表情强度或情节的影响。总之，随着静止面孔的进展，婴儿表现出更多的强烈负面情绪，但在 FFSF 的各个情节中，表情强度没有明显差异。
