Amsterdam B, Greenberg L M
Dev Psychobiol. 1977 Jan;10(1):1-6. doi: 10.1002/dev.420100102.
The reactions of 4 infants each at ages 10, 15, and 20 months were recorded on videotape as they responded to their own simultaneous video image, their own previously taped video image, the image of a control infant, and that of a female stranger. The subjects' responses were coded by 2 research assistants, ignorant of the original stimuli and the purpose of the study. The following behavioral categories were used: attends, sociable behavior, curiosity, unhappiness-withdrawal, and self-consciousness. The 1st-step discriminant according to a matrix algebra analysis between age groups was self-conscious behavior in response to the simultaneous video image. Twenty month-old infants were significantly different in their display of self-consciousness from the 10 and 15 month-old groups; the latter did not differ from each other.
研究人员用录像带记录了4名10个月、15个月和20个月大婴儿对自己同步视频影像、自己之前录制的视频影像、对照婴儿影像以及一名陌生女性影像的反应。两名研究助理对受试者的反应进行编码，他们不知道原始刺激内容和研究目的。使用了以下行为类别：注意力、社交行为、好奇心、不开心-退缩和自我意识。根据年龄组之间的矩阵代数分析，第一步判别是对同步视频影像的自我意识行为。20个月大的婴儿在自我意识表现上与10个月和15个月大的婴儿组有显著差异；后两组之间没有差异。
