Have you ever felt like your baby knows what you’re feeling before you even say a word?

Maybe you’ve noticed them light up when you’re feeling calm and happy — or pull away a little when you’re flat or overwhelmed. These little moments often feel invisible, but they’re doing more than we think.

In this episode, Dr Renee White explores new research on how a mother’s brain and her baby’s brain can literally sync up during moments of connection. Using a tool called dual EEG, researchers were able to capture real-time brain activity between mums and babies, showing that our emotional tone can directly influence how our brains work together.

This isn’t about being “on” all the time. It’s about understanding why the moments where you feel most present with your baby matter so much.

You’ll hear about:

• What brain-to-brain connection looks like between mum and baby
• Why emotional tone plays a big role in learning and development
• The science behind eye contact, cooing and everyday connection
• How maternal wellbeing supports brain synchrony
• Why it's not about perfection, but presence

What matters most is remembering that even on the tough days, your presence is powerful. You don’t have to perform. You don’t need to do more. You’re doing enough, and it’s making a difference.

Resources & Links

📲 Connect with Renee on Instagram: @fillyourcup_

🌐 Learn more about Dr Renee White and explore Fill Your Cup Doula services

🍪 Treat yourself with our Chocolate + Goji lactation cookies

If you found this episode helpful, share it with a friend or tag @fillyourcup_ on Instagram. And don’t forget to follow The Science of Motherhood so you never miss an episode.

Disclaimer:

The information on this podcast presented by Fill Your Cup is not a substitute for independent professional advice. Nothing contained in this episode is intended to be used as medical advice and it is not intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professional's advice.

[00:00:30] Dr Renee White: Hello and welcome to episode 205. This is The Science of Motherhood, and I'm your host, Dr. Renee White. In today's episode, we are exploring the fascinating science of how your brain and [00:00:45] your baby's brain literally synchronize during interaction.

[00:01:02] Dr Renee White: I have mentioned this so many times, and in particular it was in an episode with Dr. Greer Kirschenbaum. I said, wouldn't it be fascinating to have a device that you could [00:01:15] have with mother and baby to see all the amazing neuro kind of synapses and hormones going. This is kind of on the similar vein, so maybe you've noticed, uh, how your baby [00:01:30] seems to light up when you're feeling happy and engaged.

[00:02:05] Dr Renee White: So you are going to discover how positive emotions literally strengthen the connection between your two brains, [00:02:15] creating what researchers are calling a mega network that supports optimal learning. And definitely stick around for when I explain how this research reveals one mechanism through which maternal depression might affect infant [00:02:30] development.

[00:03:05] Dr Renee White: Now before we get into the study itself, let's talk about why this research is so important. Now, we know that social [00:03:15] interaction is crucial for infant development. Babies learn almost everything through their relationships, whether it be language, emotions, how to regulate their feelings, and even how to think.

[00:03:52] Dr Renee White: Now this study led by, um, Vicki Leong, um, at the University of Cambridge in the uk used a [00:04:00] technique called dual, EEG. And I'm gonna have a go at this that's Electroencephalography. And so that essentially means to record brain [00:04:15] activity from both the mother and infant simultaneously while they interacted naturally as naturally as you can with like a big cap on your head full of electrodes.

[00:04:52] Dr Renee White: Previous research had shown this happens between adults, but very little work had looked at it in [00:05:00] that parent infant pairs and critically no one had examined how the emotional quality of the interaction, whether it be positive or negative, affects this brain to brain connection. [00:05:15] Okay, let me walk you through how they did this study.

[00:05:44] Dr Renee White: [00:05:45] Now, both mum and Bub wore those EEG. Caps now these are like, just think of it like, like a swimming cap, and it's covered in electrodes that essentially measure electrical activity in the brain. And they [00:06:00] focused on 16 channels covering frontal, central and parital brain regions. And these are the areas involved in attention, emotion processing and social [00:06:15] cognition.

[00:06:36] Dr Renee White: So for the positive condition mums were asked to smile, use an upbeat, [00:06:45] enthusiastic tone, make lots of eye contact and say things like, I like this one. For the negative conditions they'd frown, use more flat or disapproving tones, um, less eye [00:07:00] contact and say things like, I don't like this. I don't like this one.

[00:07:32] Dr Renee White: So the first is PLV, so phase locking value, which measures, um, a synchronization without direction. And then they measured something called [00:07:45] PDC, which is partial directed coherence. And that, um, shows the direction of influence. So, is mum influencing baby more or vice versa? [00:08:00] And they focus particularly on, you know, six to nine hertz frequency band.

[00:08:24] Dr Renee White: Finding number one, positive emotions strengthen [00:08:30] the parent infant neural network. So when mums expressed positive emotions, their inter brain network showed significantly higher connectivity, strength and integration compared to when mothers expressed [00:08:45] negative emotions.

[00:09:02] Dr Renee White: So think of it like this. When you are happy and warm and engaged with your baby, your brains are off essentially like operating more like a unified system, [00:09:15] sharing information efficiently. So when the emotional tone is negative, that connection really weakens.

[00:09:46] Dr Renee White: So the information flow from mother to infant was significantly higher when mums were expressing positive emotions. And interestingly, during negative emotions, the pattern [00:10:00] flipped somewhat. So infants showed relatively stronger influence on that kind of dyadic network, and the researchers suggest this might be because babies increase their attention seeking behavior and visual [00:10:15] scanning when they perceive negative emotions from their mum.

[00:10:52] Dr Renee White: So for for the infants. These were essentially, you know, no differences in their own brain network [00:11:00] organization between conditions for mothers. There were some subtle changes suggesting more integrated processing during positive emotions. But these were much smaller than the inter brain effects. [00:11:15] And what this tells us is something really important and that is that the emotional quality of the interaction affects how two brains connect with each other even more [00:11:30] than it affects what's happening inside each individual brain.

[00:11:53] Dr Renee White: So when parents and babies sync up in this frequency range during positive interactions, it [00:12:00] may create an optimal state for learning and information transfer. So, what does this all mean for brain development? Now, the infant brain, as I said, is [00:12:15] incredibly plastic. You know, it's changing and forming new connections based on experience every second of the day.

[00:12:52] Dr Renee White: So your, your baby's brain is essentially borrowing processing power from your more [00:13:00] mature brain okay. So if you think about it like this, when you're in a positive emotional state together, so lots of eye contact, smiling, responsive interaction.

[00:13:39] Dr Renee White: So when babies spend more time in this positively synchronized [00:13:45] state with their caregivers, their brains have more opportunities to build the connections that support all these skills. And so conversely, when Synchrony is disrupted, which can happen with things like [00:14:00] maternal depression, stress, and other challenges in our lives, babies have, you know, they may have fewer of these optimal learning opportunities.

[00:14:34] Dr Renee White: The first thing is generally that their speech often becomes flatter in tone. They may use less eye contact. They're less responsive when their [00:14:45] baby tries to get their attention. And, you know, in, in instances, you know, they're spending less time in positive emotional states. Now all of these changes would be expected to weaken the neural connection between mother [00:15:00] and baby.

[00:15:26] Dr Renee White: And it's also a reminder of why treating maternal mental health [00:15:30] is so crucial, not just for mother's wellbeing, but for supporting optimal infant development. So, if you are experiencing depression, this isn't about guilt or blame. Depression is a medical [00:15:45] condition. These findings actually underscore why getting treatment and support is so important, not just for you, but for establishing those strong neural connections with your bubby.

[00:16:20] Dr Renee White: That's, that's, you know, neither realistic nor necessary. But during your focused interaction times, bringing that positive emotion helps [00:16:30] create that strong neural connection. Second thing I would probably say is that face-to-face time is really valuable. So this study involved direct face-to-face interactions with lots of [00:16:45] eye contact.

[00:17:19] Dr Renee White: So when you are feeling good and engaged and emotionally available, you're literally changing your baby's brain state in what that, you know, in, in ways that really [00:17:30] support their learning. Number four, this big one. It's not about perfection like really remember that this study compared positive versus negative emotional modeling, but real life isn't all one [00:17:45] or the other okay.

[00:18:12] Dr Renee White: It's about, you know, supporting [00:18:15] your ability to establish these strong neural connections with your baby. And if, if you are concerned about this, then we have got a range of resources listed in the show notes that you can connect with.

[00:18:49] Dr Renee White: The second, this was somewhat artificial task, right. So mothers were asked to deliberately model positive or negative emotions toward novel objects. [00:19:00] So I guess while this gave the researchers good experimental control, it's not quite the same as naturalistic spontaneous interaction. So future research, I guess, looking at natural emotional [00:19:15] variations would be really valuable.

[00:19:37] Dr Renee White: Finally, this was a snapshot in time. So, you know, with 10 month olds, that's quite a narrow window. We don't know [00:19:45] how these patterns of neural synchrony develop across the first year or how they relate to longer term outcomes for children all right.

[00:20:22] Dr Renee White: For parents, this underscores the importance of those moments of positive connection, the smiling, the eye contact, as I said, the warm [00:20:30] engagement for clinicians. It highlights why supporting maternal mental health is so crucial, not just for mamas, but for Bubbas as well, and for all of us. It reveals something really beautiful about human connection. We are [00:20:45] wired to literally sync up with the people that we love.

[00:21:08] Dr Renee White: If you loved this episode, please hit the subscribe button and leave a review. If you [00:21:15] know someone out there who would also love to listen to this episode, please hit the share button so they can benefit from it as well.