A mother’s love for her baby may be based on smell

BEING kept awake night-after -night, tending to a new infant, can be exhausting.

Yet most mothers not only cope with weeks and months of sleepless nights, but with the 24-hour routine of a new baby and don’t buckle under the pressure.

Maternal love has always been mooted as the reason for this Herculean strength, but a new study, from Nagasaki University in Japan, has claimed that the distinctive smell of a new baby may trigger the mother’s devotion during such a physically demanding time.

The study — published in the journal Chemical Senses — says it’s possible that the female brain is remoulded when women become mothers, and the first months of motherhood are accompanied by structural changes in brain regions including the PFC (prefrontal cortex of the brain).

“Taken together, our finding suggests that the response of the PFC toward infant odours is changed when women become mothers,” the study’s authors report.

“This could be important for mothers caring and fulfilling the unique demands of their children. And we propose that infant odours enhance mothers’ willingness to approach their infants, which then serves as an intrinsic reward.”

Child psychologist, Peadar Maxwell, says the intense feelings between mother and baby are instinctive and necessary for the survival of the species.

“What has been clear, for sometime now, is that we develop through relationships and the best first relationship is on a one-to-one basis.

“In the back and forth between a baby and her mother, there are behaviours that could always be observed, but there are also a host of biological events that involve the production of chemicals and hormones which, in turn, effect how our brain develops and our ability to self-regulate in additional relationships as we grow,” says Maxwell.

“This study highlights the need for early attachment. What is particularly encouraging is the degree to which practitioners are embracing the new scientific information and incorporating it into their work practice.”

“These new findings support what many theorists in attachment have being saying for years about the importance of the parent-child interactions on future development and relationships.”

The psychologist says neuroscience and developmental psychology, as well as mindfulness and human-attachment theory, are beginning to explain how touch, smell, feeding and play (such as cuddles, smiling, tickling) are not just pleasant experiences for the child and his parent, but are ‘transactions’ between the two.

These promote attachment neurochemicals, which help to lay down patterns of behaving and growth hormones.

“There’s lots of evidence, in current neuroscience, which confirms what is happening, in psycho-biological terms, between a mother and her baby,” he says.

“In fact, a whole new area within mental health, called interpersonal neurobiology, is attempting to bring together information from different disciplines in a way which helps us to understand the importance of the little interactions, and care-giving events, between a baby and her parents.”

Midwife Tracy Donegan believes bonding is instinctive from birth, but says new mothers also have a keener sense of smell, which accelerates this.

“Most expectant mums will readily agree that their sense of smell is heightened in pregnancy, and in labour it’s almost bionic,” she says.

“The bonding process between mother and baby is a complex interchange of hormones and sense of smell.”

Donegan says that during pregnancy the mother’s brain is ‘primed’ with special hormones, which are inactive until right after birth, when oxytocin hormone levels are at their highest and both mum and baby’s sense of smell is heightened.

“As mum’s brain changes to adapt to her new role of caring for her new baby, her baby’s brain is also adapting by recognising his mother’s unique smell and reacting to mum’s presence differently when distressed,” says Donegan. “Mother and baby are designed to be together immediately after birth to optimise these changes,” she says.

Dr Bernadette Carr — director of VHI Healthcare — says while the Japanese research is very interesting, more study needs to be done for it be conclusive.

“This report follows on from similar research carried out by the University of Montreal last year,” she says.

“While it is very likely that scent could play a significant role in how mothers and babies bond, there will likely need to be a lot more research carried out before definitive proof of how, or if, the sense of smell has such an effect on the brain response of the mother.

“Nonetheless, it is a very interesting hypothesis.”


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