As a neuroscientist specializing in emotional health and a mom of 3, I’m always curious about a child stress response and their behaviour that comes from this response. A recent study I read really got me thinking about something we all experience: conflict with our children. It turns out that how a child’s body responds during these moments of conflict might tell us a lot about their emotional struggles and behavior patterns in daily life.
This study explored something called RSA (Respiratory Sinus Arrhythmia)—a measure of how our nervous system manages stress. Researchers found that the way a child’s body reacts during an argument or disagreement with their parent can actually predict how much they struggle with emotional ups and downs or aggressive behaviors later on.
As parents, understanding this can help us shift from just managing behaviour to supporting what’s going on underneath it—how our child is experiencing and responding to stress.
What Is RSA, and Why Does It Matter?
Respiratory Sinus Arrhythmia is a measure of how the heart rate changes naturally with breathing. When we inhale, our heart rate speeds up a little; when we exhale, it slows down. This pattern is regulated by the parasympathetic nervous system, which helps the body stay calm and return to a balanced state after stress.
RSA is often used by researchers to assess how well a person can regulate their emotions, especially under pressure. High resting RSA usually means the body is calm and well-regulated. During a stressful situation, a temporary decrease in RSA (called RSA withdrawal) is normal it helps the body get ready to respond to a challenge.
But here’s the catch: too much RSA withdrawal, especially in response to everyday stressors like parent-child conflict—can be a sign that the body is overreacting. This can make it harder for a child to manage their emotions and behaviors calmly.
In this study, researchers focused on RSA because it’s a non-invasive, reliable way to look at a child’s physiological stress response, offering clues about their underlying emotional struggles. By measuring both resting RSA and changes during conflict, the study was able to identify two very different emotional and behavioral risk patterns in kids.
The Nervous System: A Window Into Emotional Regulation
Our autonomic nervous system, specifically the parasympathetic branch, helps regulate things like heart rate, breathing, and our ability to stay calm and connected. RSA is a way to track how the heart rate naturally changes with our breathing. High RSA means the body is calm and regulated. When we’re under stress, RSA decreases, a process called RSA withdrawal. This withdrawal helps us gear up to respond to a threat (think “fight or flight”).
But when this system becomes overly reactive, especially in everyday situations like parent-child disagreements, it might be a sign that a child is struggling to regulate their emotions.
This study focused on this exact idea: could a strong RSA withdrawal during conflict signal greater emotional and behavioural dysregulation in kids?
How the Study Was Done
The researchers studied 162 children around the age of 12 who were already receiving psychiatric care for mood or behavior challenges. Most of them came from diverse backgrounds and had conditions such as ADHD, depression, or anxiety.
The children were asked to participate in an 8-minute conversation with their parent about a real-life conflict (like screen time or behaviour at school), while their heart rate and RSA were monitored. This helped researchers measure the body’s response to interpersonal stress.
After that, the kids were tracked over 4 days using a phone-based survey that asked them how they felt (e.g., sad, angry, stressed) and what behaviours they used when feeling their worst (e.g., yelling, crying, hitting something).
A Strong Stress Reaction Predicted Emotional Ups and Downs
One of the most important findings was that kids who showed a bigger drop in RSA during conflict (more RSA withdrawal) were more likely to experience dysregulated basic emotions in everyday life—things like sadness, anger, stress, and nervousness. These kids weren’t just occasionally moody. They had frequent, intense emotional fluctuations—a sign of an overwhelmed nervous system.
This suggests that a child who appears “emotionally sensitive” or easily triggered may actually be showing us a deeper physiological response to stress that they haven’t yet learned how to manage.
Two Physiological Profiles, Two Different Struggles
Here’s where it gets even more interesting: the researchers found two different patterns that predicted very different outcomes. When it comes to a child stress response and their behaviour, here is what parents should understand.
1. Low Resting RSA + Big RSA Withdrawal = Emotional Vulnerability
Kids who had low baseline RSA (meaning their body was less calm to begin with) and showed a strong RSA withdrawal during conflict were more likely to experience dysregulated complex emotions, like shame, guilt, loneliness, and emptiness.
These emotions are often associated with internalizing issues, like anxiety and depression. In other words, this physiological profile may be a red flag for emotional suffering that isn’t always easy to spot on the outside.
2. High Resting RSA + Big RSA Withdrawal = Behavioral Outbursts
Kids who had high baseline RSA (meaning they were calm at rest) but showed a strong stress response during conflict were more likely to act out when overwhelmed. They were more likely to yell, cry, or physically lash out which is what the researchers called dysregulated behavior.
This profile was more aligned with externalizing issues, like reactive aggression. The child might seem okay at rest, but when stress hits, they lose control in a big way.
What This Means for Us as Parents
As a parent, this study reminded me that behaviour is a clue, not the full story. When our child yells, melts down, or even shuts down emotionally, there might be a physiological reason behind it. Their nervous system could be overreacting to stress in a way that makes it harder for them to regulate emotions or behavior in the moment.
And because this kind of physiological stress reactivity can be a risk factor for mental health issues down the road, learning to spot it early is key.
Here are a few takeaways (if you struggle with these, you might want to check out our program The Reflective Parent Club):
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If your child is highly emotional or easily overwhelmed, they may need more support with emotion regulation, not just consequences.
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Conflict is inevitable, but how we repair and co-regulate afterward matters. Staying calm can help your child’s nervous system learn how to calm down, too.
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Some kids may benefit from practicing calming strategies (like deep breathing, mindfulness, or movement) outside of conflict to help their system stay more regulated when stress hits.
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If you notice persistent emotional ups and downs or explosive behaviour, it’s worth exploring support from a psychologist or mental health professional who understands these underlying patterns.
Parenting through conflict is hard especially when our child seems to fall apart emotionally or behaviorally. But this study helped me see that these moments are more than just difficult behaviours. They’re a peek into a child’s internal world.
By tuning into our child’s stress response and their behaviour, we can start to better understand what they need to feel safe, seen, and supported.
Hear my thoughts about this article in this week’s Reflective Parenting Podcast:
I want to help parents notice how this might apply to their family and to take the next steps to grow as an emotionally resilient family. In this podcast episode, I share how a past episode of the podcast with world-renowned researcher, Dr. Marc Brackett from Yale taught us how to regulate our emotions using his RULER approach. Listen using the links below (and make sure you are subscribed to The Reflective Parenting Podcast not to miss future episodes).
Listen to this episode on Apple Podcasts
Source:
Byrd, A. L., Vine, V., Beeney, J. E., Scott, L. N., Jennings, J. R., & Stepp, S. D. (2022). RSA reactivity to parent–child conflict as a predictor of dysregulated emotion and behavior in daily life. Psychological Medicine. Advance online publication. https://doi.org/10.1017/S0033291720002810
