Data_Sheet_1_A one-hour walk in nature reduces amygdala activity in women, but not in men.pdf

Urban dwellers are more likely to develop mental disorders such as mood and anxiety disorder as well as schizophrenia compared to rural dwellers. Moreover, it has been demonstrated that even short-term exposure to nature can improve mood and decrease stress, but the underlying neural mechanisms are currently under investigation. In the present intervention study we examined the effects of a one-hour walk in an urban vs. natural environment on activity in the amygdala, a brain region previously associated with stress processing. Before and after the walk 63 participants underwent an fMRI paradigm inducing social stress. Since there is a pronounced gap in the literature regarding interindividual differences in stress-related neural effects of urban and natural environments, we set out to explore sex differences. We observed that amygdala activity decreased after the walk in nature, but only in women, suggesting that women may profit more from salutogenic effects of nature. Moreover, performance on the arithmetic tasks improved in women after the walk in nature, whereas men performed better after the walk in the urban environment. To our knowledge, this is the first study to report differencial tendencies in men and women concerning the stress-related neural activity as an effect of acute exposure to urban vs. natural environments. Furthermore, our findings highlight the importance of sex differences when exploring effects of the environment on brain function and stress. Evidence for beneficial effects of nature on stress-related brain regions may inform urban design policies to focus on providing more accessible green areas in cities and this study suggests that sex differences in experiencing the environment should be taken into consideration.

与农村居民相比，城市居民更易罹患心境障碍、焦虑障碍及精神分裂症等精神疾病。此外，已有研究证实，即便短暂接触自然环境也可改善情绪、缓解压力，但其背后的神经机制目前仍在研究之中。在本干预研究中，我们考察了在城市与自然环境中步行1小时对杏仁核（amygdala）活动的影响——杏仁核是此前被证实与压力处理相关的脑区。步行前后，63名受试者接受了一项可诱发社交压力的功能磁共振成像（fMRI）范式测试。鉴于现有文献在城市与自然环境对压力相关神经影响的个体差异方面存在显著空白，我们着手探究性别差异。我们观察到，仅在女性群体中，自然环境步行后杏仁核活动有所降低，这表明女性或许能从自然环境的健康益效中获益更多。此外，女性在自然环境步行后，算术任务的表现有所提升；而男性则在城市环境步行后表现更佳。据我们所知，本研究首次报道了急性暴露于城市与自然环境后，男女在压力相关神经活动上存在不同变化趋势。此外，我们的研究结果凸显了在探究环境对脑功能与压力的影响时，性别差异的重要性。有关自然环境对压力相关脑区有益影响的研究证据，可为城市设计政策提供参考，助力城市打造更多可及的绿色空间；同时本研究也提示，在体验环境的过程中，性别差异应当被纳入考量范畴。