Dr. Sarah King, ND
@sarahhealthyfox

How human touch, trust, and emotions are linked with oxytocin

Everyone needs hugs! Think about it: Describe that feeling you get when cuddling up with your partner or getting a well-needed hug from someone you love. That feeling is likely being enhanced via increased oxytocin levels. Midwives, doulas and childbirth educators refer to oxytocin as the “cuddle hormone.” It promotes milk letdown, helps prevent postpartum hemorrhage and increases uterine contractions during labor. We also know that it facilitates the emotional bond between mother and infant, but new research is showing the effect this hormone has on our social behaviour and response to emotional stimuli from childhood to adulthood.

Oxytocin During and Post Labour

After birth, newborns placed skin-to-skin with their mother have a very predictable pattern of behaviour. First, they start moving their little bodies, wiggling and inching towards mother’s breasts. Then based on light to crude touch, their rooting reflex kicks in as they move their heads back and forth to find the nipple. Lastly, sucking begins which increases oxytocin levels in the mother. However, infants have adapted an additional behaviour to increase these levels.

A 2001 study showed that infants will rhythmically massage his/her mother’s breasts to help facilitate oxytocin release before sucking¹. The intensity of the hand movement was linked to serum oxytocin levels which would fall again after motion and sucking ceased. Knowing that this type of “warm touch” (massaging breasts and nipples) can increase oxytocin levels, birth partners are often encouraged to perform nipple stimulation to assist in labour or help move along a sluggish labour.

Oxytocin and the Parent-Infant/Child Attachment

While there are physical cues to oxytocin release in labouring women or those who have just given birth, we also need to keep in mind the factors that influence oxytocin receptor upregulation. These receptors are largely found in the amygdala of the brain and are responsible for emotional processing, social reward and cognitive empathy². We are beginning to understand how maternal oxytocin can affect a mother’s response to her own child, but we must realize the factors involved: Endogenous secretion of oxytocin, and the gene expression of oxytocin receptors or dysfunction thereof.

During pregnancy there is increased upregulation of these oxytocin receptors, however, low levels of circulating oxytocin and/or a genetic disposition for decreased receptor upregulation can both lead to poor mother-child bonding². Low maternal oxytocin has been linked to a decreased reward signal to their infant², so mothers with low oxytocin levels will put less significance on her baby’s sensory cues. With an emotional disconnection to her baby, this can result in lower oxytocin levels in the child². It is curious how this will shape the child’s social adaptation knowing the effect of oxytocin on the brain.

We are starting to understand its effect in moulding social behaviour, trust and the ability of children to recognize facial expressions in relation to emotions. New research is looking into the connection between oxytocin levels and Autism Spectrum Disorders (ASD) as it may be an influential factor in social cognitive behaviour^3,4.

Oxytocin, Sexual Relationships and Preparing for Children

With the role of oxytocin in emotional processing and social reward, one study looked to see what it would do for married couples. For partners in an emotional relationship, the act of “warm-touch” (cuddling, hand-holding and hugging) communicates affection but has also been linked to a decrease in all-cause mortality⁵. In this study, women who reported more frequent hugs from their partners also had higher serum oxytocin levels⁵. When comparing groups who engage more in warm-touch (based on at-home recordings), salivary oxytocin levels measured after cuddling activity were increased.

With oxytocin being so strongly linked to the amygdala and recognition of social stimuli, we know how crucial it is to parent-infant bonding. This further sets up the relationship as the child grows older and must encounter facial recognition of emotions, develop trust and increase positive communication. But not only is oxytocin essential for proper childhood development but we’re beginning to discover its role in adult relationships and how this will affect future offspring.

This year, let’s use Valentine’s day as a reminder that we all need hugs and (consensual) physical touch. It influences our whole social world and in recognizing trust in others. Without it it’s easy to feel isolated or alone. Love is everywhere: mothers and daughters, fathers and sons, husbands, wives, girlfriends, boyfriends and best friends. Let’s not forget about affection and how to respectfully show it. It’s a form of communication more important than we may realize: a signal of emotional security and a hormone regulator passed on to our young.

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Dr. Sarah King is a licensed Naturopathic Doctor, graduating from the Canadian College of Naturopathic Medicine in 2014. Prior to completing her medical studies, she attended Nipissing University where she received her Honors Bachelor of Science in Biology. Sarah has a passion for women’s health and is a birth doula in Durham and Toronto Region. She treats a wide variety of health conditions including menstrual disorders and hormone balancing, fertility, prenatal care, digestive concerns, skincare and mental health/anxiety. Outside the office Sarah is an avid runner with a love of the GTA’s best forest trails. She also continues to improve her yoga practice and teaches breath work as part of stress management counselling to her patients.

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References:

1. Matthiesen, Ann-Sofi, Anna-Berit Ransjo-Arvidson, Eva Nissen, and Kerstin Uvnas-Moberg. “Postpartum Maternal Oxytocin Release by Newborns: Effects of Infant Hand Massage and Sucking.” Birth 28.1 (2001): 13-19. Web.
2. Herpertz, Sabine C., and Katja Bertsch. “A New Perspective on the Pathophysiology of Borderline Personality Disorder: A Model of the Role of Oxytocin.” American Journal of Psychiatry AJP 172.9 (2015): 840-51. Web.
3. Quattrocki, E., and Karl Friston. “Autism, Oxytocin and Interoception.” Neuroscience & Biobehavioral Reviews 47 (2014): 410-30. Web.
4. Preti, Antonio, Mariangela Melis, Sara Siddi, Marcello Vellante, Giuseppe Doneddu, and Roberta Fadda. “Oxytocin and Autism: A Systematic Review of Randomized Controlled Trials.” Journal of Child and Adolescent Psychopharmacology 24.2 (2014): 54-68. Web.
5. Holt-Lunstad, Julianne, Wendy A. Birmingham, and Kathleen C. Light. “Influence of a “Warm Touch” Support Enhancement Intervention Among Married Couples on Ambulatory Blood Pressure, Oxytocin, Alpha Amylase, and Cortisol.” Psychosomatic Medicine 70.9 (2008): 976-85. Web.