The Nurture Science Program at Columbia University Irving Medical Center studies the mechanisms and benefits of mutual mother-child sensory-emotional interactions, and their impact on socioemotional and physical health.
Our Family Nurture Intervention (FNI) has now been shown to increase vagal tone in moms and babies up to 5 years after the intervention. This makes FNI the first randomized control trial (RCT) in the NICU to demonstrate short and long term positive effects in both infant and mother, across multiple domains at multiple time points, out to 5 years.
We’re very excited about these new findings published in PLOS One, and we wanted to share with you what our lead researchers—Dr. Martha G. Welch MD and Dr. Michael M. Myers PhD—have to say about FNI and its long term implications.
What is Family Nurture Intervention (FNI)?
Dr. Welch: We developed FNI to address the risks inherent in a NICU stay for both preterm infants and their mothers. Our hypothesis is that establishing autonomic co-regulation and emotional connection between mothers and babies helps them overcome the stressors of these traumatic experiences. And that’s what we showed, and published in this PLOS One paper—that cardiac regulation, a known risk in these infants and mothers, is improved even 5 years after this intervention.
FNI facilitates sensory and emotional interactions to re-establish autonomic connection between mother and baby. This goes beyond previously-studied singular interventions (like the wonderful kangaroo care or mothers giving scent cloths to their babies), by prioritizing mutual sensory exchange to facilitate emotional expression during repeated co-calming sessions.
The control group in our study received standard care in the NICU, with encouragement to engage in established beneficial interventions, as well as access to psychologists and social workers. In addition to receiving standard care, mothers in the FNI group were supported by trained nurture specialists, who helped them connect through:
- Mutual Sensory Calming: comfort touch, exchange of scent cloths (so mothers got one from their babies as well), vocal soothing, and skin-to-skin contact when feasible, as a vehicle for
- Emotional Expression: using a series of nurture prompts tailored for families in this difficult setting, mothers used infant-directed speech to tell their infants about their experiences and feelings, preferably in their primary language. For example: “Tell your baby the story of your pregnancy and birth.”
What Were the Results?
Dr. Myers: One truly remarkable finding was better physiological regulation. As measured by heart rate variability (HRV), FNI babies had faster maturation of vagal tone up to term age, which we published about previously, but now we know that at 4-5 years post-intervention, they and their mothers still had better vagal tone than SC mothers and children. In an earlier paper, FNI mothers also showed fewer symptoms of anxiety and depression, and demonstrated more sensitive caregiving behaviors.
Dr. Welch: Many physicians are rightfully concerned with prefrontal cortical impairments in preterm children—emotion regulation, impulse control, executive function. In our prior work we measured brain activity, and that’s where we saw the largest effects: FNI babies showed more rapid maturation of brain activity and earlier decrease in coherence (“higher coherence” might sound like a good thing, but in this context low coherence together with higher EEG power has been shown to predict better outcomes).
At 18 months (a time point predictive of future outcomes) the babies also scored better on three well-established screens, demonstrating fewer attention problems, better cognitive and language development, and decreased risk for socioemotional problems.
Dr. Myers: And we’re talking about roughly 6 hours of intervention per week in the NICU, with no further intervention once they’re discharged. Degree of prematurity didn’t matter, sex didn’t matter, twin status didn’t matter, and many of our results were independent of demographic factors. So this is a really powerful intervention. Recently, we’ve been able to replicate these brain activity results, and we’re excited to announce that Family Nurture Care is becoming standard care in University of Texas Health Sciences Center San Antonio, and The Valley Hospital Association in New Jersey, with plans for New York Presbyterian Morgan Stanley Children’s Hospital Level IV NICU (at Columbia).
Dr. Welch: It’s very exciting. FNI is the first NICU-based intervention to show long term improvements in neurodevelopment, behavior, and vagal regulation in both the baby and the mother. And it’s because our intervention is co: co-regulation, co-calming, the autonomic nervous systems of two people.
Why Vagal Tone?
Dr. Myers: The vagus is the primary nerve in the autonomic nervous system, and allows for bidirectional communication between brain and gut. High vagal tone is a marker of capacity for prosocial behavior. Being prosocial, being emotionally connected, is good for you, and really good for your heart. It’s physiologically protective somehow. And early measures of vagal tone in children do predict better school performance.
There’s no non-invasive way to measure vagal nerve activity to and from the gut, but the branch that goes to the heart has an indirect index: heart rate variability, or vagal tone—that, we can measure. You need a computer and some tricks, but it’s easy to get to and very objective. So to some extent, we’re looking at that because it’s what we can do, but it’s also directly related to what we’re interested in: vagal tone is a mental and physical health marker.
Dr. Welch: Yes, and vagal tone is a measure ofautonomic function, which is central to development. When mother and baby co-regulate their autonomic nervous systems, that connection is lifelong unless it’s disrupted.
Dr. Myers: We’ve known for a long time that mother-infant autonomic connection is conditioned in utero, by signaling and responding to each other’s changes: fetuses learn their mother’s voice, they learn smells, learn about the environment—they’ll actually show preferences for foods their mother eats.
Dr. Welch: And at full-term, the two continue their autonomic responses to each other and it builds this fundamental connection. But when a baby is born preterm, all those interactions that normally take place after birth get disrupted by the prolonged separation of a NICU stay. If disruption happens, you must repair it.
Dr. Welch: Co-regulation is autonomic and fundamental. It’s a direct approach to interrupting the stress response. Because it stimulates parasympathetic function, it has all kinds of crucial benefits like facilitating growth and development, calming gut inflammation, modulating stress responses, and improving cardiac function, immune response, sleep, and memory.
Dr. Myers: Mother-infant interaction has been studied in animal models for decades, but no one has done a comprehensive study on separation of (and the resulting long term consequences on) human mothers and babies. The separation in NICU is necessary to save the baby’s life, and we’re so grateful for that technology, but it’s very stressful: these mothers are at increased risk of anxiety and depression, the babies have delays in cognitive, language, and behavioral development, and both have increased cardiac risk.
It really runs the gamut. If you don’t have good vagal regulation, you’re at risk for all kinds of things, including death following heart attack.
Dr. Welch: That’s why our findings are so important. FNI, which targets the autonomic nervous system and its vagus nerve, decreases all of these risks.
The improved physiology of the mothers is very important, because mothers who have preterm babies are at added risk for cardiovascular disease later on. Since we’ve established higher vagal tone, which is associated with long term cardiac health, we’re buffering them against these risks, now, at least 5 years in the future, and we hope, longer.
By positively affecting the physiology of both mother and child for the long term, Family Nurture Care helps protect them against stress and adversity, and redirects them both toward optimal cardiac function, executive function, and overall health.
Can This Benefit Full-Term Babies and Their Mothers, Too? This Seems Pretty Universal.
Dr. Myers: Yes, absolutely. With regard to the PLOS One paper, 5-year follow-ups are not common in this kind of work. That timeframe actually kind of blew me away. There are so many things that happen between discharge and five years of age. To see physiologic changes that are measurable, and to find that they’re there in the mother as well, makes it quite a remarkable finding. It’s not a one-off flash in the pan; we have an effect for a while. This is something that can change lives for a long time. Just like we have lactation specialists, we need nurture specialists. This is experiential; it’s not didactic. You don’t give the mothers a book to read, or anything. In fact, it’s the antithesis of things: you want no things, no toys, between mother and child. Just them. It’s all about them.
Dr. Welch: The theory of change and the proposed mechanism underlying how this works makes this applicable not just to preemies, but to full-term babies, to older kids… to human beings. We all need co-regulation.