Breastfeeding: Test Your Knowledge-- True or False?

The important human function of breastfeeding is the subject of many myths and misunderstandings. A fascinating meld of biological and behavioral events, it’s worth the attention of everyone interested in early development, even those who will not be participating at the adult end. Test your knowledge of breastfeeding by reading these “true or false?” questions.

1. Breastfeeding helps the baby resist infectious diseases. True or false?

Very true! Although babies are born with a supply of antibodies they got from their mothers’ immune systems, those antibodies can only protect against diseases the mother had already been exposed to, not exposure to new diseases after the birth. In addition, those antibodies will have diminished by the time the baby is about 8 months old, a point at which infants do not yet do a good job of making their own antibodies. The nursing mother acts as an “auxiliary immune system” to her infant. She supplies more of the antibodies she already had, and if the nursing pair are exposed to a new disease, the mother’s efficient immune system goes to work to produce antibodies and pass them on to the baby in her milk. What if the baby is exposed to something, and the mother not exposed to it? Don’t worry, she will be exposed quickly, because the physical intimacy of nursing (and other infant care) means she will come into contact with the baby’s mucus, urine, and feces.

Do note that the baby can still use this kind of help toward the end of the first year. Babies who live in clean conditions, with modern food supplies and access to modern medicine, are less affected by a lack of breastfeeding, but those living in primitive conditions may die of infections that could have been prevented by breastfeeding.


2.Nursing mothers need to eat a lot more than usual. True or false?
It depends on the conditions. If the mother was well nourished during the pregnancy, she has laid down extra fat and extra calcium in her bones, and these will be used to support lactation, so she needs little if any extra food. If the mother is living at a subsistence level, she will need extra calories to compensate for those consumed by the baby. An ounce of human milk has about 20 calories on the average, so you can do the math, considering the amount of milk consumed by babies of different sizes and ages.

The nursing mother does need to drink a lot more fluid than when she is not breastfeeding. Every ounce of fluid the baby takes needs to be replaced. Many nursing mothers automatically go to drink a glass of water before they pick up the baby to nurse, or have a cup of tea while breastfeeding. Traditionally, nursing mothers drank dark beers like porter, which supplied extra fluid and a hefty dose of B vitamins, and gave everyone a nice nap too-- nowadays we tend to frown on this, and certainly this practice would have its dangers if it occurred more than once in a while .

3. You can’t breastfeed a baby once he or she gets teeth. True or false?

False. Babies can easily be taught not to bite the nipple, if the mother is vigilant (and believe me, after one bite she WILL be vigilant). Biting and sucking take different jaw movements, and an attentive mother can see when a sucking baby re-adjusts its jaw position in preparation for a chomp. The mother then gently inserts her finger between the baby’s jaws, toward the back of the mouth. This breaks the suction, so the baby cannot get any milk, and if he or she bites down, there’s not much satisfaction, because those itchy teething gums are in the front. Within 24 hours, the baby will have learned that although you can bite lots of things, you can’t bite that nipple-- it just doesn’t work.

Nursing mothers really have to teach biting babies not to bite, or their nipples can actually be damaged, and the baby will have to be weaned from the breast.

4. Nursing babies don’t like the milk that’s flavored by strong-tasting foods their mothers have eaten. True or false?

This is mainly false, with some possible individual exceptions. The taste researchers Menella and Beauchamp fed a group of nursing mothers an all-garlic-flavored lunch, waited a couple of hours, and then timed how long the babies nursed. When they compared this to nursing time after a bland lunch, they found that the babies actually nursed longer when the milk had a garlic flavor.

There may be some individual differences, with particular babies possibly disliking certain flavors. One important point is that when a nursing mother has had a mild breast infection, the milk on that side seems to be a little saltier than usual, and babies may not care for it-- to the mother’s frustration, as frequent thorough nursing is a help in clearing up these problems.

Hey Good-Lookin': About Newborns Recognizing Their Mothers

I recognized a friend at a restaurant last night. We walked quickly toward each other, hugged, called each other by name, and began to dish the gossip. Other people watching (if any) would have agreed-- yes, they recognized each other.

But, of course, people who say newborn babies recognize their mothers don’t mean they do any of those grown-up things. I want to take some space here to talk about exactly what they do mean.

The first issue is what things babies can do that could let us tell whether they recognize someone. Their hearing is quite good, normally. Even before they’re born they show that they have heard something by sudden movements. After they’re born, they can choose a sound to listen to if we give them an artificial nipple rigged so their sucking can trigger one sound or another. Their vision is not as good as their hearing at birth-- detail vision is not what it will later be, and the clearest images they get are of objects about 12 to 18 inches from the eyes. They have some preferences for what they look at, and show those by looking longer at certain things, especially faces. They have excellent capacities for smell and taste, too, but those are much more difficult to work with because a particular smell or taste may linger for quite a while and is not so easy to change.

Newborns have another highly relevant ability: they are able to habituate and dishabituate to a sensory stimulus. This is a cognitive skill that may be the foundation of all other thinking. Basically, a baby habituates when he or she stops looking at or paying attention to a sight or sound that has been going on for a while. Dishabituation occurs when a new stimulus replaces the old one and the baby begins to look and pay attention once again. Young babies are much interested by novelty and on the whole pay more attention to unfamiliar than to familiar things-- a much different situation than we see in older children or adults, who like to examine familiar things very closely.

Habituation seems to apply to all senses and begins very early in life. For example, in one study, preterm babies held unfamiliar shapes in their hands longer than they did familiar ones (Lejeune, F. et al., [2010], The manual habituation and discrimination of shapes in preterm human infants from 33 to 34+6 post-conceptional age. PLoS ONE, Vol. 5, 1-7). And when it comes to measuring recognition, habituation is a real complicating factor, as ordinarily very young babies show more interest in unfamiliar things and less in familiar things, raising the possibility that “recognition” might be defined as ignoring something rather than paying attention to it. Nevertheless, studying habituation lets us see whether a baby responds differently to two faces or voices, and differences in response are enough to let us know whether there is recognition.... but not all research takes habituation into account or uses it as a way to understand the baby's reactions.

In one study, babies 2-4 days old showed different movements in response to their mothers’ voices and strangers’ voices, and also to their mothers’ voices speaking in an adult-directed way versus their mothers speaking “motherese” with its high pitch and exaggerated intonations. But when similar recordings were made of unborn babies (about 36 weeks gestational age) as they listened to their mothers’ or strangers’ voices from a speaker placed on the mothers’ abdomens, the babies did not react differently to mothers and strangers; on the other hand, they did react differently to the mother’s voice through the speaker and the mother’s voice when she was actually talking (Hepper, P.G., & Shahidullah, S. [1993]. Newborn and fetal rersponse to mother’s voice. Journal of Reproductive and Infant Psychology, Vol. 11, 147-153).

Anthony DeCasper is a researcher well-known for his 1986 work on recognition of mother’s voice and even of the “Dr. Seuss” story she read to her belly toward the end of pregnancy. He has continued to explore this topic and has found, not too surprisingly, that it’s all more complicated than it would appear. For example, in a recent study (Decasper, A.J., & Prescott, P. [2009]. Lateralized processes constrain auditory reinforcement in human newborns. Hearing research, Vol. 255, 135-141), he showed that the baby’s response to different sounds depends on which ear is being used, and therefore on which hemisphere of the brain is receiving messages about the sound. DeCasper provided the babies with a sucking device that could detect and record how fast the baby sucked. Faster sucking could produce one sound for the baby to hear, slower sucking a different sound. The sounds included an unfamiliar voice speaking, a recording of what the mother’s heartbeats sound like inside the uterus, and the mother’s voice speaking in either her native language or a different language.

Here are the complicated findings: When the baby had a choice between a stranger’s voice and the heartbeat, it chose the stranger’s voice only when listening with the right ear (through an earphone). It chose the heartbeats only when listening with the left ear. When the choice was between the mother’s voice and a stranger’s voice, or between the mother speaking her native language and speaking a foreign language, the baby chose the more familiar sound only when listening with the left ear. These findings suggest that when the baby is listening with both ears-- in its ordinary non-laboratory situation-- familiarity alone will not govern his or her attention and behavior. “Recognizing” does not seem to be such a simple matter.

Finally, I want to talk about a study that used habituation as part of its measure of babies’ looking preferences and ability to “recognize” (Figueiredo, B., et al. [2010]. Mother’s anxiety and depression during the third pregnancy trimester and neonate’s mother versus stranger’s face/voice visual preference. Early Human Development, Vol.86, 479-485). This study recorded how long a baby looked directly at its mother, who had spoken, as opposed to how long it looked at a stranger, who also spoke. (They were not present or speaking at the same time.) At the beginning of the study, the babies looked at the mothers for an average of 9.7 seconds, and at the strangers for an average of 6.8 seconds. When tested again a bit later, after habituation had taken place, they looked at the mothers for an average of 6.1 seconds and at the strangers (a different stranger than the one originally used was brought in for this) for 9 seconds. This suggests that they were socially competent enough to tell the difference between the mother and the stranger, but they had no overwhelming need to be attentive to the mother. Their recognition could be shown by the fact that they looked less at the mother rather than more.

A second, very interesting part of this study compared the behavior of babies whose mothers were anxious or depressed during pregnancy with that of those who were not. Newborns of depressed or anxious mothers showed much less “recognition” in the form of different amounts of looking toward their mothers and toward strangers. The impact of those differences on maternal attitudes and on the development of relationships may be a matter of concern, and suggests an emphasis on the transactional nature of development, in which mothers and babies influence each other in ways that change with time and experience.

Symbiosis, Intersubjectivity, and Early Relationships

When people concerned about adoption discuss relationships between babies and mothers, they sometimes refer to a period of symbiosis, in which the identities or “selves” of mother and child are somehow fused, so the baby cannot tell the self from the mother effectively. As I’ve pointed out before, this idea is derived from the work of Margaret Mahler and other psychoanalytically-oriented thinkers, who considered this symbiotic period to last from about the second month to the seventh month or so. It’s important to note that Mahler herself did not think the symbiotic period included the first weeks of life or that the events of that period would have any effect on babies who were separated early from their birth mothers and adopted into different families.

Daniel Stern, in The Interpersonal World of the Infant, refers to symbiosis and discusses the concept in detail, but points out that modern research on early development has revealed a number of phenomena that contradict the possibility of early symbiosis as “fusion”. I want to review a number of facts that suggest that babies have an early concept of “self” versus “other” that makes a sense of fusion unlikely for the baby (although mothers may feel that their “selves” include their babies). This sense has been referred to as “primary intersubjectivity”.

One thing that suggests that young babies already “know” (or act as if they know) the difference between the self and another is that shortly after birth they will imitate the facial expressions of others, opening their mouths, even sticking out their tongues (Meltzoff, A., & Moore, A. [1989]. Imitation in newborn infants: Exploring the range of gestures imitated and the underlying mechanisms. Developmental Psychology, 25, 954-962). It is difficult to imagine that a baby would imitate itself (which brings to mind some infinite progression of mirrors), so the great majority of developmental psychologists today would interpret imitation as some primitive awareness that there are other people “out there”. Incidentally, this newborn imitation is not confined to the mother’s facial expressions as we might expect if the birth mother already had overwhelming importance for the infant.

Another point contradicting the possibility of “fusion” and symbiosis is the infant’s response to the so-called “still-face” situation. In this situation, an adult (the mother or someone else) faces a baby, but does not make eye contact and maintains a blank and unresponsive demeanor (this is not easy to do when the baby is signaling that it wants attention, by the way). From a few months of age, babies are distressed by this and become disorganized in their behavior, whimpering, averting the gaze, looking at their hands, even hiccupping. Babies who are in the developmental period where symbiosis had been thought to occur change their behavior in response to the still-face rather than accepting the unresponsiveness as a part of the “fused selves”.

At the same time, though, mothers or other primary caregivers continue to act as if they feel fused with their young babies. They interpret baby sounds, looks, and gestures as if they (the mothers) know the babies’ intentions. They talk to the baby about his or her needs and feelings. When talking to other adults, they may “speak for the baby”, voicing what they feel to be the babies’ opinions and answering questions or comments made to the baby by other adults. Sometimes they begin their baby remarks by saying “Say” in a lower voice, then switching to a high voice for the words the baby is supposed to mean to say (“Yes, I’m sleepy, Grandma”). As so often occurs, the mothers’ feelings and behavior are parallel to and supportive of the babies’ actions, but are by no means the same.

It’s notable that mothers’ sense of fusion fosters good infant development at the same time that it is not actually in line with reality. The mother who interprets her infant’s signals fairly accurately is encouraging the development of communication, followed by speech and eventually by other cognitive abilities. If she felt “unfused”, was convinced that the baby did not intend to communicate or that she could not understand, and did not try to respond, the mother would not do such a good job and the baby’s development might well be slowed. Problems are likely to occur when the mother is too depressed, tired, or sick to be responsive, or when there are too many young children to care for at once (as in low-quality group care for infants).

Even infants of a few months notice differences in adult emotional facial expressions, but they don’t respond with concern for the worried or frightened adult. By 8 or 9 months, they are interested in the meaning the adult’s emotions have for the child (is there something to be afraid of?). But it’s not until 12 months or so that they begin to have “theory of mind”-- the assumption that other people have their own separate feelings and knowledge, and that those adult facial expressions indicate feelings inside the adult. Without theory of mind, infants can hardly feel a sense of intimacy, much less symbiotic emotional fusion, with adults.

It’s a problem to assume that mothers’ and babies’ feelings about each other are mutual, with each a mirror of the other. We can’t make good guesses about infant abilities just from knowing how adults function. Research on infant abilities tells us that no matter what mothers may feel, babies don’t experience symbiosis. However much adoption reform is needed, it would not be wise to make reforms based on the assumption that mothers and young infants are in symbiotic relationships.