Cerebral Synchronization Between Mothers and Their Newborns During Breastfeeding

Cerebral Synchronization Between Mothers and Their Newborns During Breastfeeding and Related Oxytocin Response, According to Different Reciprocal Positioning of the Dyad, and Possible Related Benefit for Postpartum Depressive Symptoms

Different reciprocal positions of mother and newborn during breastfeeding may be adopted. Other than the one derived from UNICEF guidelines, or standard position, an approach called biological nurturing has been recently proposed. It aims to promote the activation of neonatal primitive reflexes, breast problems reduction (e.g. cracked or sore nipple) and, overall, spontaneity and naturalness of mother-newborn dyad behaviour during feeding.

The study of newborn cortical activation by functional near-infrared spectroscopy (fNIRS), a safe and minimally invasive functional neuroimaging technique based on haemoglobin absorption of near-infrared light, showed that baby's cortex exhibit a wide activation associated with breastfeeding. Moreover, preliminary and not yet published data, collected by fNIRS hyperscanning (e.g. the simultaneous detection of brain functional activation from two individuals living the same experience) in the Nursery of our Institute, evidenced that mother-newborn dyads adopting a biological nurturing approach to breastfeeding show a neural synchronization between their frontal cortex during such experience. Basing on this new evidence, it is now worth to understand if a biological nurturing approach to breastfeeding may promote such neural synchronization, even when postpartum depressive symptoms are present. Accordingly, biological nurturing may result to be protective for the neural basis of mother-newborn relationship, also in case of a postnatal affective suffering and helping to prevent its potential long term consequences on maternal wellbeing and infant neurodevelopment as well. Moreover, since oxytocin is a neuropeptide with widespread influence on parental function, including lactation and nurturing maternal behaviour physiology, if a biological nurturing approach to breastfeeding may promote the oxytocin level in the mother and/or in the newborn is worth to understand as well, taking into account again possible relations with postpartum depression symptoms. the aim of this study is to evaluate, by fNIRS hyperscanning, if the frontal cerebral cortex functional synchronization of mother-newborn dyads, who adopt a reciprocal positioning according to the biological nurturing approach during breastfeeding, differs from that of mother-newborn dyads adopting the standard position, taking into account the intensity of mother's postpartum depressive symptoms.

Breastfeeding is a very important experience since the beginning of life, supplying the best physical, biological and affective conditions for newborn's growth and development. Its promotion of motor, cognitive (e.g. language, memory), and emotional development in the long term was also observed. Benefits are for the mother too, including a reduction of the risk for postpartum depression. This clinical condition is the most common maternal psychiatric disorder after childbirth, observed in 10%-15% of mothers, and may adversely affect mother-newborn relationship, psychophysical maternal wellbeing, and infant development.

Different reciprocal positions of mother and newborn during breastfeeding may be adopted. Other than the one derived from UNICEF guidelines, or standard position, an approach called biological nurturing has been recently proposed. It aims to promote the activation of neonatal primitive reflexes, breast problems reduction (e.g. cracked or sore nipple) and, overall, spontaneity and naturalness of mother-newborn dyad behaviour during feeding.

Newborn cortical activation associated with breastfeeding was studied too. By functional near-infrared spectroscopy (fNIRS), a safe and minimally invasive functional neuroimaging technique based on haemoglobin absorption of near-infrared light, our research group showed that baby's cortex exhibit a wide activation associated with breastfeeding. Moreover, preliminary and not yet published data, collected by fNIRS hyperscanning (e.g. the simultaneous detection of brain functional activation from two individuals living the same experience) in the Nursery of our Institute, evidenced that mother-newborn dyads adopting a biological nurturing approach to breastfeeding show a neural synchronization between their frontal cortex during such experience. Basing on this new evidence, it is now worth to understand if a biological nurturing approach to breastfeeding may promote such neural synchronization, even when postpartum depressive symptoms are present. Accordingly, biological nurturing may result to be protective for the neural basis of mother-newborn relationship, also in case of a postnatal affective suffering and helping to prevent its potential long term consequences on maternal wellbeing and infant neurodevelopment as well. Moreover, since oxytocin is a neuropeptide with widespread influence on parental function, including lactation and nurturing maternal behaviour physiology, if a biological nurturing approach to breastfeeding may promote the oxytocin level in the mother and/or in the newborn is worth to understand as well, taking into account again possible relations with postpartum depression symptoms. the aim of this study is to evaluate, by fNIRS hyperscanning, if the frontal cerebral cortex functional synchronization of mother-newborn dyads, who adopt a reciprocal positioning according to the biological nurturing approach during breastfeeding, differs from that of mother-newborn dyads adopting the standard position, taking into account the intensity of mother's postpartum depressive symptoms.

Inclusion Criteria:

1. Full term healthy newborn
2. Weight > 2500 gr
3. Vaginal delivery
4. Breastfeeding already started
5. Absence of breast problems (e.g. cracked or sore nipple)
6. Parents' consent to research participation

Exclusion Criteria:

1. Syndromic diagnosis (genetic/hereditary)
2. Condition affecting a major organ (heart disease, cerebropathy, etc.)
3. Medication intake that may interfere with the data collection (e.g. analgesics)
4. Newborn head lesion that may interfere with the fNIRS assessment (e.g. due to an operative delivery)
5. Mother history of neurological or neurosensory disorder, psychosis, bipolar disorder, and substance abuse or addiction.