Maternal odor is known to play an important role in mother-infant-interaction in many altricial species such as rodents. However, we only know very little about its role in early human development. The present study therefore investigated the impact of maternal odor on infant brain responses to emotional expression. We recorded the electroencephalographic (EEG) signal of seven-month-old infants watching happy and fearful faces. Infants in two control groups exposed to no specific odor (control 1) or the odor of a different infant’s mother (control 2) showed the expected EEG fear response. Crucially, this response was markedly absent in the experimental group exposed to their mother’s odor. Thus, infants respond differently to fear signals in the presence of maternal odor. Our data therefore suggest that maternal odor can be a strong modulator of social perception in human infants.

众所周知，在许多啮齿动物中，母体气味在母婴互动中起着重要作用。但是，我们对其在人类早期发展中的作用知之甚少。因此，本研究调查了母体气味对婴儿大脑对情绪表达的反应的影响。我们记录了七个月大的婴儿在观看快乐和恐惧表情时的脑电图（EEG）信号。在两个对照组中，没有特殊气味（对照组1）或其他婴儿母亲的气味（对照组2）的婴儿表现出预期的EEG恐惧反应。至关重要的是，暴露于母亲气味的实验组中明显没有这种反应。因此，在母体气味存在下，婴儿对恐惧信号的反应不同。