认知能力对于儿童接受教育以及学习新知识都具有非常关键的作用，同时也决定着儿童人力资本的形成。儿童认知能力的提高，不仅会对自身的发展产生积极影响，对未来的职业发展以及收入水平的提高具有重要的促进作用，同时也有利于社会进步。近年来随着学生升学压力的增大，“内卷”现象愈发明显，越来越多的妈妈选择放弃工作成为全职妈妈专心照顾家庭，从而有更多的时间来照料孩子并引导、监督孩子学习。但是成为全职妈妈后，虽然妈妈可以付出更多时间照顾子女，督促子女学习，但也可能会对儿童认知能力的提升存在消极影响。因此，本文使用CFPS2016年与CFPS2018年的调查数据进行固定效应回归，研究母亲选择成为全职妈妈对儿童认知能力的影响。

首先，本文就所研究样本的儿童及家庭特征状况进行了统计描述；通过方差分析探究了不同特征下的儿童在各项认知能力测试，包括记忆测试、数列测试、识字测试、数学测试上的得分均值是否存在显著性差异；通过独立性检验来探讨选择成为全职妈妈的比例在不同特征的人群中是否存在差异；利用方差分析探讨了全职妈妈对儿童的影响。数据显示：四项认知能力在家庭经济水平、教育期望、关心孩子教育频率、主动与孩子沟通频率方面都存在着显著性差异，且大致都呈现正相关的关系；是否选择成为全职妈妈存在显著的城乡差异，会受到孩子性别孩子学段、母亲受教育程度以及家庭收入水平的影响；与非全职妈妈相比，全职妈妈过去12个月与孩子居住的平均时间多1.07个月，但关心孩子教育的频率以及主动与孩子沟通的频率并未有显著的提高。

其次，本文构建了固定效应回归模型，结果显示：儿童的母亲选择成为全职妈妈后在0.1显著性水平下会对儿童的认知能力产生显著的负向影响，系数为-0.316，整体而言，成为全职妈妈后对儿童认知能力发展所产生的陪伴效应小于收入效应以及其他消极因素带来的影响。机制分析结果显示，母亲在成为全职妈妈后，会显著降低人均家庭纯收入水平，进而不利于儿童认知能力的发展，故降低人均家庭纯收入水平可能是全职妈妈降低儿童认知能力的潜在机制。

然后，本文进行了异质性分析。研究发现，低年龄儿童比高年龄儿童在母亲是否成为全职妈妈的选择上受到了更大的消极影响；全职妈妈对儿童认知能力所产生的消极影响主要存在于认知能力较低的儿童群体中；全职妈妈对儿童认知能力的影响存在家庭经济水平的异质性，对于较低收入水平家庭成为全职妈妈会对儿童认知能力的发展产生显著的负向影响，而对于较高收入水平家庭的全职妈妈则不存在这一负向影响；全职妈妈的受教育程度越高，越有利于儿童认知能力的发展；在不同的与孩子沟通频率下，全职妈妈对儿童认知能力的影响均不显著。

最后，针对研究结论提出如下建议：（1）结合实际情况，谨慎选择是否成为全职妈妈。当家庭经济水平以及妈妈受教育程度较低时，母亲要充分考虑实际情况，避免成为全职妈妈后给儿童的发展带来消极影响。（2）注重科学的家庭教育，提高陪伴质量。父母应该学习一些家庭教育的理论知识，让家庭教育变得更加科学、专业化以及针对性，提高陪伴的质量。（3）适度监督与引导，营造良好的家庭氛围。全职妈妈要运用合理的教养方式，要结合孩子的实际情况，适度对孩子进行引导与监督，提高孩子学习的自驱力与积极性，并注重子女心理健康。（4）全职妈妈要注重自身发展，降低消极情绪影响。对于全职妈妈而言，可以根据家庭经济情况以及与孩子的相处情况，适度恢复社会交往，将部分注意力转移到自身发展与自我价值上，减少消极情绪对孩子的负面影响。

Cognitive ability plays a crucial role in children's education and learning new knowledge, and also determines the formation of children's human capital. The improvement of children's cognitive abilities not only has a positive impact on their own development, but also plays an important role in promoting future career development and income levels, and is beneficial to social progress. In recent years, with the increasing pressure on students to pursue higher education, the phenomenon of "involution" has become increasingly apparent. More and more mothers choose to give up work and become full-time mothers, focusing on taking care of their families, so that they have more time to take care of their children and guide and supervise their learning. However, after becoming a full-time mother, although mothers can spend more time taking care of their children and supervising their learning, it may also have a negative impact on the improvement of children's cognitive abilities. Therefore, this article uses survey data from CFPS 2016 and CFPS 2018 for fixed effects regression to study the impact of mothers choosing to become full-time mothers on children's cognitive abilities.

Firstly, this article provides a statistical description of the children and family characteristics of the studied sample; We explored through analysis of variance whether there were significant differences in the mean scores of children's cognitive ability tests under different characteristics, including memory tests, sequence tests, literacy tests, and mathematics tests; Exploring whether there are differences in the proportion of choosing to become full-time mothers among populations with different characteristics through independence testing; The impact of full-time mothers on children was explored using analysis of variance. The data shows that there are significant differences in the four cognitive abilities in terms of family economic level, educational expectations, frequency of caring for children's education, and frequency of active communication with children, and they all show a roughly positive correlation; There is a significant urban-rural difference in whether to choose to become a full-time mother, which is influenced by the child's gender, educational level, and family income level; Compared to non full-time mothers, full-time mothers have spent an average of 1.07 months more time living with their children in the past 12 months, but their frequency of caring about their children's education and actively communicating with them has not significantly increased.

Secondly, this article constructed a fixed effects regression model, and the results showed that the choice of a child's mother to become a full-time mother had a significant negative impact on the child's cognitive ability at a significance level of 0.1, with a coefficient of -0.316. Overall, the accompanying effect of becoming a full-time mother on the child's cognitive development was smaller than the impact of income and other negative factors. The mechanism analysis results show that after becoming a full-time mother, mothers will significantly reduce the per capita family net income level, which is not conducive to the development of children's cognitive abilities. Therefore, reducing the per capita family net income level may be a potential mechanism for full-time mothers to reduce children's cognitive abilities.

Then, this article conducted heterogeneity analysis. Research has found that younger children are more negatively affected than older children in their mother's choice of becoming a full-time mother; The negative impact of full-time mothers on children's cognitive abilities mainly exists in children with lower cognitive abilities; The impact of full-time mothers on children's cognitive abilities exhibits heterogeneity in family economic levels. Becoming a full-time mother for low-income families has a significant negative impact on the development of children's cognitive abilities, while full-time mothers for high-income families do not have this negative impact; The higher the education level of full-time mothers, the more conducive it is to the development of children's cognitive abilities; The impact of full-time mothers on children's cognitive abilities is not significant at different communication frequencies.

Finally, in response to the research findings, the following suggestions are proposed: (1) Based on the actual situation, carefully choose whether to become a full-time mother. When the family's economic level and the mother's education level are low, the mother should fully consider the actual situation to avoid negative impacts on the child's development after becoming a full-time mother. (2) Emphasize scientific family education and improve the quality of companionship. Parents should learn some theoretical knowledge of family education to make it more scientific, professional, and targeted, and improve the quality of companionship. (3) Moderate supervision and guidance, creating a good family atmosphere. Full time mothers should use reasonable parenting methods, combine with their children's actual situation, moderately guide and supervise their children, improve their children's self motivation and enthusiasm for learning, and pay attention to their children's mental health. (4) Full time mothers should focus on their own development and reduce the negative emotional impact. For full-time mothers, they can moderately restore social interaction based on their family's economic situation and their interaction with their children, shift some attention to their own development and self-worth, and reduce the negative impact of negative emotions on their children.