Department of Psychology, Northwestern University, USA.
Horm Behav. 2013 Sep;64(4):673-84. doi: 10.1016/j.yhbeh.2013.08.003. Epub 2013 Aug 17.
Most men have a category-specific pattern of genital and subjective sexual arousal, responding much more strongly to erotic stimuli depicting their preferred sex than to erotic stimuli depicting their nonpreferred sex. In contrast, women tend to have a less specific arousal pattern. To better understand this sex difference, we used neuroimaging to explore its neural correlates. Heterosexual and homosexual women viewed erotic photographs of either men or women. Evoked neural activity was monitored via fMRI and compared with responses to the same stimuli in heterosexual and homosexual men. Overall, a network of limbic (as well as the anterior cingulate) and visual processing regions showed significantly less category-specific activity in women than men. This was primarily driven by weaker overall activations to preferred-sex stimuli in women, though there was also some evidence of stronger limbic activations to nonpreferred-sex stimuli in women. Primary results were similar for heterosexual and homosexual participants. Women did show some evidence of category-specific responses in the visual processing regions, although even in these regions they exhibited less differential activity than men. In the anterior cingulate, a region with high concentrations of sex-hormone receptors, subjective and neural category specificity measures correlated positively for women but negatively for men, suggesting a possible sex difference in the role of the anterior cingulate. Overall, results suggest that men tend to show more differentiated neural responses than do women to erotic photographs of one sex compared to the other sex, though women may not be entirely indifferent to which sex is depicted.
大多数男性的生殖器和主观性唤起都有特定的类别模式，对描绘他们偏好性别的色情刺激的反应比描绘他们非偏好性别的色情刺激要强得多。相比之下，女性的唤起模式往往不那么具体。为了更好地理解这种性别差异，我们使用神经影像学来探索其神经相关性。异性恋和同性恋女性观看了男性或女性的色情照片。通过 fMRI 监测诱发的神经活动，并将其与异性恋和同性恋男性对相同刺激的反应进行比较。总的来说，边缘（以及前扣带）和视觉处理区域的网络在女性中的类别特异性活动明显少于男性。这主要是由于女性对偏好性刺激的整体激活较弱所致，尽管也有一些证据表明女性对非偏好性刺激的边缘激活较强。主要结果对异性恋和同性恋参与者都是相似的。女性在视觉处理区域确实显示出一些类别特异性反应的证据，尽管即使在这些区域，她们的活动差异也比男性小。在前扣带，这个区域有高浓度的性激素受体，主观和神经类别特异性测量在女性中呈正相关，而在男性中呈负相关，这表明前扣带的作用可能存在性别差异。总的来说，结果表明，与女性相比，男性在观看某一性别与另一性别的色情照片时，倾向于表现出更分化的神经反应，尽管女性对所描绘的性别可能并非完全漠不关心。
