学者们通常认为，女性在排卵期性欲会增强，在月经期性欲会降低。近日，北京大学医学部胡佩诚教授等的研究却得出了相反的结论：在女性最容易受孕的排卵期，与性相关的神经活动水平显著下降；而在月经期，与性相关的神经活动水平与平时无明显差异。该研究结果近日在线发表于《行为大脑研究》（Behav Brain Res）。

据高嵩副教授介绍，女性对男性的心理反应会受到月经周期的影响，以往多以问卷调查或访谈的方式来研究这一问题，由于受试者主观影响通常得出矛盾的结果。过去人们认为，在排卵期，女性的性欲会增强，这样可以增加受孕机会，提高生育率，有利于物种繁衍。

胡佩诚等应用功能磁共振成像技术，观察了15位女性在处理视觉性刺激时大脑的神经反应，研究了月经周期对于女性大脑处理视觉性刺激的影响。研究发现，与预期不同，在女性最容易受孕的排卵期，与性相关的神经活动水平显著下降；而在月经期，与性相关的神经活动水平与平时无明显差别。

研究人员以性别对抗理论解释了研究结果，即女性在进化过程中是“有意”地从生理和心理上隐藏其排卵期，目的在于提升其从男性那里获得的照料水平，并隐藏子代的血缘关系，从而提高婴儿的安全性。这类隐藏排卵期的现象多见于由多个成年雄性和多个雌性组成群落的灵长目物种；相反，在由1个成年雄性和多个雌性组成群落的物种，如大猩猩和黑猩猩，雌性有显著的排卵标志。另一种可能的解释是妊娠会使女性付出巨大代价，所以在受孕可能较大的排卵期，女性会在完全不自觉的情况下变得更加慎重。（生物谷Bioon.com）

生物谷推荐原始出处：

Behavioural Brain Research doi:10.1016/j.bbr.2009.09.027

Brain activation evoked by erotic films varies with different menstrual phases: An fMRI study

Xun Zhua, Xiaoying Wangb, c, Carolyn Parkinsond, Chengxu Caie, Song Gaob, ,  and Peicheng Hua, ,

aDepartment of Medical Psychology, Peking University Health Science Center, No. 38, Xueyuan Road, Haidian District, Beijing 100191, China
bBeijing Key Lab of Medical Physics and Engineering, Peking University, Haidian Chengfulu 201, Beijing 100087, China
cDepartment of Radiology, Peking University First Hospital, No. 8, Xishiku Street, Xicheng District, Beijing 100034, China
dDepartment of Psychological and Brain Sciences, Dartmouth College, 6207 Moore Hall, Hanover, NH 03755, USA
eDepartment of Chemistry, Renmin University of China, No. 59, Zhongguancun street, Haidian district, Beijing 100872, China

In humans, fluctuating hormone levels throughout the menstrual cycle are believed to regulate many cyclical sexual behaviors and motivational processes. However, there is a dearth of research investigating the neural correlates of this phenomenon. We used functional magnetic resonance imaging to identify brain regions involved in sexual arousal's regulatory process. Fifteen female participants were scanned while viewing erotic film excerpts at three time points during a single menstrual cycle: ovulation, menstruation, and at one additional time point. Tripled two-group differences analysis revealed that significant activation in the comparison was observed in non-ovulatory phases of the menstrual cycle in parts of the right inferior frontal gyrus, right lateral occipital cortex, and left postcentral gyrus, as well as in the bilateral superior parietal lobule. Thus, our results indicate that brain activity differs in the ovulatory phase of the menstrual cycle compared to during other menstrual phases. This finding provides neurological evidence for the ovulatory cycle's modulation of the processing of the sexual arousal in female human brain.

转载本文请联系原作者获取授权，同时请注明本文来自黄志恒科学网博客。
链接地址：https://m.sciencenet.cn/blog-266677-274066.html

上一篇：[医护心情]致卫生局局长，上海市市长的一封信：2010年上海医学毕业生强烈呼吁，不要仓促全面推行“住院医师
下一篇：李开复：大一时美国打工惊魂遭遇