孕妇更长计远虑?——怀孕对女性跨期决策偏好的影响

Are Pregnant Women More Foresighted? The Effect of Pregnancy on Intertemporal Choice

文章基于行为决策和进化心理学理论,分3个研究逐步推进,探讨了怀孕对女性跨期决策偏好的影响,并检验了未来取向在其中的中介作用。研究1对真实孕妇与未孕女性进行了准实验设计,探讨了怀孕女性与未孕女性在未来取向与跨期决策上的差异;研究2排除了生理激素的干扰,在实验室启动育龄女性怀孕心理状态,进一步验证了怀孕心理因素对未来取向和跨期决策偏好的影响;研究3操纵了未来取向水平,验证了未来取向与跨期决策之间的因果关系。3个实验的结果发现,怀孕女性比未孕女性的未来取向更高,在跨期决策中更加偏好远期选项。这表明:女性怀孕后,作为母亲这一角色会引发对未来生活和未来事件的详细思考,形成一种有利于后代延续及基因传承的"母性思维"(maternal mind)。在这种思维模式下,怀孕女性在跨期决策时更加长期偏好,存在"长计远虑"效应。

People often have to consider and compare the importance of different things that occur at different time points and then make decisions. When making intertemporal choices, individuals have to choose between a smaller and sooner reward （SS） and a larger and later reward （LL）. Pregnancy as a critical life event inevitably comes with a series of physiological and psychological changes. We hypothesized that such changes would make the pregnant women more future oriented and hence would reduce their delay discounting. We tested our hypotheses by using a quasi-experiment design （Study 1） and an experiment design （Study 2）. Pregnant women were recruited in Study 1, and non-pregnant women were primed with maternal mind set in Study 2. In both studies, control groups were non-pregnant women without any manipulation. All the participants in both studies completed the Consideration of Future Consequences Scale （Strathman, Gleicher, Boninger, ＆ Edwards, 1994; Gt = 0.71） and Intertemporal Decision-making Tasks （Wang ＆ Dvorak, 2010）. In Study 3, we manipulated future orientation to determine whether it was causally related to intertemporal decision. The manipulations in Study 2 and Study 3 were both successful. They showed that pregnant women were more future-oriented than their peer control groups. Pregnant women had a much lower delay discounting rate in intertemporal decision-making. Furthermore, it was found that the level of future orientation mediated this effect. This research explored the differences in intertemporal choice between pregnant women and their peer group. Our results revealed that pregnant women had a ＇maternal mind＇ which focuses more on future events. This mindset promotes future-orientation and a greater preference for LL options in intertemporal choice.