Albin-Brooks Christopher, Nealer Connor, Sabihi Sara, Haim Achikam, Leuner Benedetta
Department of Psychology, The Ohio State University, Columbus, OH 43210, USA.
Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA.
Horm Behav. 2017 Mar;89:130-136. doi: 10.1016/j.yhbeh.2016.12.015. Epub 2017 Jan 4.
Pregnancy and the postpartum period are times of profound behavioral change including alterations in cognitive function. This has been most often studied using hippocampal-dependent tasks assessing spatial learning and memory. However, less is known about the cognitive effects of motherhood for tasks that rely on areas other than the hippocampus. We have previously shown that postpartum females perform better on the extradimensional phase of an attentional set shifting task, a measure of cognitive flexibility which is dependent on the medial prefrontal cortex (mPFC). The present experiments aimed to extend this work by examining the importance of postpartum stage as well as offspring and parity in driving improved mPFC cognitive function during motherhood. We also examined whether the neuropeptide oxytocin, which plays a role in regulating numerous maternal functions, mediates enhanced cognitive flexibility during motherhood. Our results demonstrate that compared to virgin females, cognitive flexibility is enhanced in mothers regardless of postpartum stage and is not affected by parity since both first (primiparous) and second (biparous) time mothers showed the enhancement. Moreover, we found that improved cognitive flexibility in mothers requires the presence of offspring, as removal of the pups abolished the cognitive enhancement in postpartum females. Lastly, using an oxytocin receptor antagonist, we demonstrate that oxytocin signaling in the mPFC is necessary for the beneficial effects of motherhood on cognitive flexibility. Together, these data provide insights into the temporal, experiential and hormonal factors which regulate mPFC-dependent cognitive function during the postpartum period.
怀孕和产后时期是行为发生深刻变化的阶段，包括认知功能的改变。这一点最常通过评估空间学习和记忆的海马体依赖性任务来进行研究。然而，对于母亲身份对依赖海马体以外区域的任务的认知影响，我们了解得较少。我们之前已经表明，产后雌性在注意力集转换任务的维度外阶段表现更好，这是一种认知灵活性的测量指标，它依赖于内侧前额叶皮质（mPFC）。本实验旨在通过研究产后阶段以及后代和产次在推动母亲身份期间mPFC认知功能改善方面的重要性来扩展这项工作。我们还研究了在调节众多母性功能中起作用的神经肽催产素是否介导了母亲身份期间认知灵活性的增强。我们的结果表明，与未生育的雌性相比，无论产后阶段如何，母亲的认知灵活性都会增强，并且不受产次影响，因为初产（头胎）和经产（二胎）母亲都表现出了这种增强。此外，我们发现母亲认知灵活性的提高需要有后代的存在，因为移除幼崽会消除产后雌性的认知增强。最后，使用催产素受体拮抗剂，我们证明mPFC中的催产素信号对于母亲身份对认知灵活性的有益影响是必要的。总之，这些数据为调节产后时期mPFC依赖性认知功能的时间、经验和激素因素提供了见解。
