Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany; Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Research Center Jülich, Wilhelm-Johne Strasse, 52425 Jülich, Germany.
Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, Uniklinik RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany; Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Research Center Jülich, Wilhelm-Johne Strasse, 52425 Jülich, Germany; Department of Clinical Neuroscience, Karolinska Institutet, Tomtebodavägen 18A, 171 77 Stockholm, Sweden.
Neuroimage. 2021 Apr 1;229:117733. doi: 10.1016/j.neuroimage.2021.117733. Epub 2021 Jan 21.
Female chemical signals underlie the advertising of sexual receptivity and fertility. Whether the body odor of a pregnant woman also has a signaling function with respect to male behavior is yet to be conclusively established. This study examines how the body odors of ovulating and pregnant women differentially affect the behavior of heterosexual men. Body odor samples were collected from 5 pregnant women and 5 matched controls during ovulation. In a double-blind functional magnetic resonance imaging design, 18 heterosexual men were exposed to female body odors during ovulation (OV) and pregnancy (PRG) while being required to indicate the attractiveness of concurrently presented female portrait images. The participants were also required to indicate whether they assumed a depicted woman was pregnant. While neither OV nor PRG altered the perceived attractiveness of a presented face, the men tended to identify the women as pregnant while exposed to a PRG body odor. On the neural level, OV activated a network of the frontotemporal and limbic regions, while PRG activated the superior medial frontal gyrus. The results suggest that the detection of sexual availability activates the male brain regions associated with face processing and reward/motivation, whereas sensing pregnancy activates a region responsible for empathy and prosocial behavior. Thus, the female body odor during pregnancy likely helps foster circumstances conducive to the future care of offspring while the body odor advertising sexual availability promotes mating behavior. The brains of heterosexual men may be capable of unconsciously discriminating between these two types of olfactory stimuli.
女性的化学信号是性行为接受度和生育能力的标志。孕妇的体味是否对男性行为具有信号功能，目前尚未得出明确结论。本研究旨在探讨女性排卵和妊娠时的体臭如何影响异性恋男性的行为。从 5 名孕妇和 5 名匹配的对照组女性在排卵期间采集了体臭样本。在一项双盲功能磁共振成像设计中，18 名异性恋男性在排卵（OV）和妊娠（PRG）期间暴露于女性体臭中，同时需要对同时呈现的女性肖像图像的吸引力进行评分。参与者还需要判断他们是否认为所描绘的女性怀孕了。OV 和 PRG 均未改变呈现面孔的感知吸引力，但男性在暴露于 PRG 体臭时倾向于将女性识别为怀孕。在神经水平上，OV 激活了额颞叶和边缘区域的网络，而 PRG 则激活了上内侧额回。结果表明，检测到性可用性会激活与面部处理和奖励/动机相关的男性大脑区域，而感知到怀孕则会激活负责同理心和亲社会行为的区域。因此，女性在怀孕期间的体臭可能有助于营造有利于未来照顾后代的环境，而体臭则宣传性可用性，促进交配行为。异性恋男性的大脑可能能够无意识地区分这两种类型的嗅觉刺激。
