The bond between mother and child

Research shows that without a secure motherly attachment, children's bodies activate a stress reaction to unexpected events.

By Beth Azar
Monitor staff
With the cutting of the umbilical cord, physical attachment to our mothers ends and emotional and psychological attachment begins. While the first attachment provides everything we need to thrive inside the womb, many psychologists believe the second attachment provides the psychological foundation and maybe even the social and physical buffer we need to thrive in the world.

Psychologists' research shows that the quality of care infants receive affects how they later get along with friends, how well they do in school and how they react to new, and possibly stressful, situations.

The psychological construct of attachment, developed in the late 1950s, describes how babies become attached to their primary-care giver, usually their mothers. Securely attached babies consider 'Mom' a safe base from which to explore their environment.

They gain assurance from her presence and use her as a source of comfort when they are distressed or upset. Insecurely attached babies seek comfort from their mothers, but gain less assurance from her.

Attachments infants and children form with other primary-care providers also affect a child's development, research shows. The nature and impact of such attachments have become a focus for researchers interested in the increase in daycare for very young children.

Social development

Many researchers have found correlations between secure mother-infant attachment and later psychological and social development. Infants who securely attach to their mothers become more self-reliant toddlers and have a better sense of self-esteem, said Alan Sroufe, PhD, an attachment researcher at the Institute of Child Development at the University of Minnesota.

He's been following a group of 180 disadvantaged children-now age 19-since before birth, looking at mother-infant attachment and multiple developmental measures such as the kids' expectations from relationships with parents and friends. He's also looking at the children's life stress, success in school and peer relationships.

Sroufe has found that even though these children lead unstable lives, if they had a secure mother-infant attachment they were likely to be self-reliant into adolescence, have lower rates of psychopathology, enjoy successful peer relationships through age 16 and do well in school-especially in math-at all ages.

Sroufe doesn't think infant attachment affects aptitude, but he believes it affects confidence, attitude and, subsequently, attendance and achievement.

His sample has more life stress and less social support than the average, middle-class samples most researchers study. He's found that this stress-including instability and loss-can deflect even the most positive life course.

'Kids who had secure attachment histories but suffer losses will become less secure,' said Sroufe.

He also found that anxious, poorly attached infants can become more secure if their mothers enter stable love relationships or alleviate their symptoms of depression.

Buffering stress

Secure infant attachment may provide children with a crucial tool for dealing with stress by buffering their physiological reaction to novel or unexpected events, said Megan Gunnar, PhD, of the Institute of Child Development at the University of Minnesota.

To test this theory, Gunnar exposes children to mildly stressful events and measures changes in their stress-related hormones. An increase in the hormone cortisol, for example, indicates an extreme stress reaction.

In a recent study now in press, Gunnar, along with her then- graduate student Melissa Nachmias, PhD, and others, exposed 77 18-month-old children to three stimuli that the children could choose to approach or avoid: a live clown, a robot clown and a puppet show. Mothers were always present, but for the first three minutes with each stimulus researchers asked them not to participate. For the second three minutes, researchers told the mothers to try to comfort their children.

After the experiment, researchers measured cortisol levels in the children's saliva. A week later, the researchers measured mother-child attachment using the 'strange-situation' test (a commonly used measure of attachment).

As expected, the researchers found no increase in cortisol for children who approached the stimuli without fear. However, cortisol levels for inhibited children, who appeared scared and wouldn't approach the stimuli, varied depending on their attachments to their mothers. Inhibited children who had secure attachments showed no increase in cortisol while inhibited children with insecure attachments showed an increase.

'The secure children seemed to be saying, 'This is scary but I feel safe,'' said Gunnar. 'They had the resources to cope.'

Mothers of more inhibited children differed dramatically in how they responded to their child's distress. Mothers of socially attached children were able to calm their children immediately. They seemed to have an established history with the child that didn't require any work.

But mothers with insecure attachments were working hard to get their fearful children to not be fearful, said Gunnar. 'They seemed to think it was their job to change the child, to make the child look bold.'

In a similar real-life experiment, also in press, Gunnar measured cortisol in about 60 toddlers who received inoculations from a physician. She again found that only fearful, insecure children exhibited increased salivary cortisol.

Secure attachments may act as a buffer against the stress of new, strange or scary events, Gunnar said. Without that buffer, children find it difficult to cope and their bodies activate a stress reaction.

No attachment

And what happens if there is no motherly attachment? Psychobiologist Mary Carlson, PhD, of Harvard Medical School, asked that question when she went to Romania last September to measure cortisol levels in orphans.

Many Rumanian mothers can't afford to care for a newborn, and send their children directly from the hospital maternity wards to orphanages. The children receive little to no physical or emotional stimulation from the caretakers in the orphanages. She worked with two groups of 30 children. As part of another study, one group received enriched care-one adult for four children-for a year, six months prior to Carlson's visit. The other group received standard 20-child-to-one-adult care the entire time.

On an average day for a typical child, cortisol levels peak in the morning and decrease by the end of the day. In both groups of orphans, however, cortisol levels increased from morning to noon and decreased slightly by evening.

There were slight differences

for the children who received the enriched care, but because it ended six months before Carlson could study them, there's no way to know if the care had positive effects that then diminished when the children returned to standard care.

Rhesus monkeys reared with a 'surrogate mother' made of a wire frame covered by cloth-a poor mother substitute-demonstrate abnormal cortisol cycling similar to those of the Rumanian orphans, according to experiments by Gunnar and Stephen Suomi, PhD, Thomas Boyce, PhD, and Maribeth Champaux, PhD, at the National Institute for Child Health and Human Development.

Gunnar wanted to know if the monkeys simply cycled improperly, or if it was a matter of 'no mommy, no attachment, no buffer.' So, she and her colleagues repeated the experiment, making sure to keep the monkeys' environment unusually quiet-removing even normal daily movements around the lab. The monkeys produced normal cycles.

For these severely deprived monkeys, any stimulation seems to cause stress; they have no buffer to cope with even normal, daily events, said Gunnar.

These studies show that the most basic biological systems depend on social stimulation early in life, said Carlson. Without it, children lack the foundation to deal with everyday life, let alone trauma and stress.

Beyond the mother

With more children entering daycare, researchers have begun to look beyond mother-infant attachment to primary caregiver attachment, whether it be a mother, father or daycare provider.

'If you take the notion that children form attachments from the daily mundane experiences of care-feeding, diaper changing, caressing-you need to look at all the caregivers,' said Carollee Howes, PhD, at the University of California, Los Angeles.

In a series of studies, Howes found that the attachments children form with their primary caregivers is remarkably similar to the attachments they form with their mothers.

However, secure attachments only occur with 50 percent of caregivers as opposed to 70 percent of mothers. The lower rate of attachment probably reflects the lower quality and closeness of the caregiver relationship, said Howes.

In terms of effect, Howes and her colleagues found that in a group of 48 4-year-olds, attachment to a child-care provider better predicted peer interactions than mother-child attachment. Toddlers with secure attachments to teachers were more gregarious and more likely to engage in pretend play with peers; preschoolers were more sociable. Children with insecure teacher attachments were more hostile, aggressive, antisocial and withdrawn.

'Attachments are relationships that develop from interactions,' said Howes. 'We have to figure out who the caregivers are' and make sure they're all competent.

While this is a relief to mothers who want or have to work, it also emphasizes the need for high- quality child care, Howes pointed out.

Many attachment researchers find themselves playing the part of child advocates, they admit. Their research points to the need for social policies that allow mothers to stay home or that require high-quality daycare for all children.

'Babies need a lot of love and a lot of work, and denying that would be wrong,' said Sroufe.

PsycNET 2009 American Psychological Association