How Does Maternal Depression Affect Young Babies?

When I’ve mentioned maternal depression on this blog, I’ve sometimes been quite surprised to have readers respond as if the condition was a moral failure rather than a mental illness. That attitude was especially common when the reference was to depression in adoptive mothers-- some seemed to think that such women were simply spoiled brats who changed their minds about what they wanted after they discovered that baby care was a challenge. I don’t think there’s much point to arguing about that belief. Depression is more common in women than in men, and is especially common during the child-bearing years. Although some women who are depressed while caring for young babies have been depressed earlier in their lives, it is also true that life-changing events-- even much-wanted ones-- can trigger depressive reactions, however counter-intuitive that may be.

Mood disorders in young mothers can exist for a variety of reasons. But it doesn’t really matter whether they occur because of moral turpitude or because of a genetically-determined emotional disturbance. In all cases, effective treatment is desirable, because a depressed caregiver cannot provide the foundation for a baby’s good cognitive and emotional development.

Why is this? How can a very young baby even know what a caregiver’s mood is? And as long as it’s fed, warm, and clean, why would the baby care?

To answer these questions, it’s important to look very closely at communications between caregivers and young babies-- communications that are quite subtle and occur very quickly, so a casual observer can notice only a few, if any, of them. Understanding such communications requires a microanalysis of videotaped movements and facial expressions. These can be examined in the order in which they occurred, so it’s possible to see how each member of the pair responded to changes in the other. (As an example of this, I’m going to summarize an article by Reck, Noe, Stefenelli, Fuchs, and others, “Interactive coordination of currently depressed inpatient mothers and their infants during the postpartum period”, Infant Mental Health Journal, 2011, Vol. 32, pp. 542-562.)

Ideally, we’d expect the baby and the caregiver to be coordinated in their behavior and mood, and to respond to each other by matching a communicated mood (what Edward Tronick calls mutual regulation). But we’d also expect that the two will occasionally make mistakes or “mismatches” and respond with a smile to a frown, or vice-versa. Normally, baby and caregiver fairly quickly notice their mistakes and “repair” the communication by moving to match the other’s mood more closely. Those repair events seem to be even more important than frequent accurate matches, because they teach the baby that moods can be changed and regulated, and that mistaken communications can be corrected with effort.

Reck and her co-authors looked at a group of mothers who were hospitalized together with their babies for treatment of serious depression, and compared them to a group of healthy mothers and their infants. They observed the frequency of positive matches (when both partners showed positive emotion) and negative matches (when both showed negative emotion such as crying, withdrawal, hostility, or intrusiveness). Because it has been reported that maternal depression interferes with the development of joint attention (looking at an object and then back at each other), shared looking at objects was also studied. There was particular interest in the pairs’ abilities to repair mismatches and come to similar positive states. The babies ranged from 1 to 8 months in age.

In order to encourage mothers and babies to show their social interactions, the researchers used the “face-to-face still-face” method. In this, mother and baby were seated opposite each other, with one video camera recording each face’s expressions and a single microphone between them. The mothers were instructed to begin just with a normal interaction, to get the babies’ attention and play with them without using toys or a pacifier. After two minutes of this play, the mothers were to do two minutes of an unresponsive “still face”, in which they simply stare into space toward the baby without responding to the baby’s bids for communication. For the final two minutes (the “reunion” phase), the mothers were to return to normal responsiveness and engage with the baby again.

Depressed mothers and their babies did behave somewhat differently from healthy mothers with their babies. When the mother was depressed, repair of mismatches took longer. Healthy mothers were quicker to repair mismatches in the reunion phase than in the initial play phase, as if they were “trying harder” after the difficult period of the still-face episode, but when mothers were depressed the difference was the opposite. There were also differences in the time it took the mother-baby pairs to come to a match. For the healthy mother-baby pairs, half of them got to a positive match in 3 seconds after they began, whereas in half of the cases with depressed mothers they needed 12 seconds to get to a positive match in the play episode and 18 seconds in the reunion episode.

The babies of depressed mothers thus had quite different experiences of social interactions than did those of healthy mothers-- and experiences of this kind would be repeated many thousands of times in the early months of life in ordinary caregiving. Slower development of communication skills would certainly be expectable for babies of depressed mothers. This would be only one of several reasons why treatment of maternal depression is important with respect to infant development. Babies don’t have to know their mothers’ moods, or to care about them-- they are affected by depression in their caregivers in ways that do not support the best development.