The Science of Why Babies Cry More and What Parents Need to Know

You may have noticed that your baby sometimes seems calm and relaxed…and then goes through a ‘fussy’ phase, where they seem to cry no matter what you do.  Do these fussy phases happen on a predictable schedule?  Is it predictable for all babies…and for all parents?   In this episode, we dive into the research behind the theory of the Wonder Weeks, as described in the books and app. This popular concept suggests that all babies experience predictable periods of fussiness in preparation for going through developmental ‘leaps,’ but the science behind it may be much more limited than you expect. We break down the available research, explain why babies might cry more at certain stages, and help parents understand the truth about these so-called Wonder Weeks.  

What topics do we cover?

• How Wonder Weeks became a popular theory
• What actual research says about baby crying phases
• Ways to support your baby during fussy times, whether or not Wonder Weeks apply

  By the end, you’ll feel more informed about why babies cry and have a clearer idea of whether Wonder Weeks is a useful tool for understanding your baby’s needs.   Episodes Mentioned:

• SYPM 016: Getting it right from the start with a new baby 
• Episode 138: Most of What You Know About Attachment is Probably Wrong
• Episode 72: What is RIE?
• Episode 084: The science of RIE
• Episode 173: Why we shouldn’t read the Your X-Year-Old child books anymore
• Episode 137: Psychological Flexibility through ACT with Dr. Diana Hill
• Episode 075: Should we Go Ahead and Heap Rewards On Our Kid?
• Episode 066: Is the 30 Million Word Gap real?
• Episode 072: Is the 30 Million Word Gap Real: Part II
• Episode 031: Parenting beyond pink and blue
• Episode 017: Don’t bother trying to increase your child’s self-esteem

  Books mentioned in this episode:

The Wonder Weeks by Dr. Frans  Plooij and Hetty van de Rijt

  Jump to Highlights: 00:03 Introduction to the Podcast and Wonder Weeks 02:19 Background on the Plooys and Their Research 05:43 Methodology and Findings of the Plooys' Study 10:20 Criticisms and Limitations of the Plooys' Study 20:11 Replication Studies and Their Findings 59:42 Conclusions and Implications   References: Aldridge, J. Wayne, et al. "Neuronal coding of serial order: syntax of grooming in the neostriatum." Psychological Science 4.6 (1993): 391-395.

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Alink, L. R. A., Mesman, J., van Zeijl, J., Stolk, M. N., Juffer, F., Koot, H. M., Bakermans-Kranenburg, M. J., & van IJzendoorn, M. H. (2006). The early aggression curve: Development of physical aggression in 10- to 50- month old children. Child Development, 77(4), 954-966.

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Bell, Martha Ann, and Christy D. Wolfe. "Emotion and cognition: An intricately boun