Smiles and Your Baby's Brain

Positive, happy, smiling looks are vital to the growth of your baby’s brain. In case that’s too easy to miss, I’ll use the lazy tool of repetition to make sure it’s easy to take home this take home message. A smile doesn’t only make him ‘feel better’ (sounds a bit vague), doesn’t only ‘distract him’ when he’s upset: smiles are vital to the growth of your baby’s brain (Gerhardt, 2004). Studies on different areas of the brain and nervous system (neuroscience) and on the hormone systems can now provide evidence to explain our innate parenting behaviours and also to demonstrate how crucial they are to the brain’s development. Wonderful! It’s good to hear that what you already do is fantastic! Congratulations! By ‘innate parenting behaviours’, it is usually meant: smiling at your baby, copying their actions, making the same noises to them that they make to you, hugging your baby, soothing your baby to help him regulate his emotions when he is distraught. In essence, responding to your baby’s cues as often as possible is essential for the development of his brain.

Your Baby Needs to Attach to You…

You may have heard of John Bowlby and his Attachment Theory. His idea was that a baby has a developmental need – not just an ‘emotional’ need, whatever that might be – for a ‘secure base’ (Bowlby, 1988). He believed that without knowing that there is a predictable someone who can see him and respond to him, the baby will struggle to develop a secure sense of self. Observational studies of the behaviour of parents, with follow up studies of the growing children, demonstrated that clinginess, neediness and a tendency towards separation anxiety in adult relationships correlate well with a lack of responsiveness from parents in infancy (Dettling, 2002). Based on his research, Bowlby believed that the need for an ‘attachment figure’ was as important as the need for food, for warmth, or for sleep. Responsive parenting is the means by which we communicate that we are that needed attachment figure. Even though he didn’t have the scientific explanations for his theory, it has been enormously influential.

…So That His Brain Can Develop

And now, we do know why. The brain is a relational organ. Right. So what does this mean? Let’s use the example of smiling at your baby. A baby has an innate attentiveness, from birth, towards faces and facial expressions. When you look at your baby positively, he sees that your pupils are dilated (as you are feeling pleasurable feelings of love) and innately recognises this signal. His nervous system is activated in response, his heart rate goes up, and he releases neurochemicals into an area of his brain. The neurochemicals cause pleasurable feelings in your baby; but that’s not all. They also glucose to be taken up in this area of the brain, which encourages growth of new tissue (Gerhardt, 2004).  So when I say ‘the brain is a relational organ’, I mean that in the absence of loving and positive responses from a parent, the brain develops in a decidedly non-optimal environment and its growth is literally stunted. It’s a beautiful (and simplified, for the sake of poetry!) concept: baby’s brain is built on smiles.

What If Baby Can’t Attach…?

So what happens to prevent this process which I’ve so cavalierly called ‘innate’? Because the truth is, many parents do not find it easy or instinctive to respond to their baby’s cues or to smile at their baby. Maybe they never learned this behaviour because their own parents couldn’t do it with them (you can’t do something until you’ve learned it). Maybe they are suffering with postnatal depression and it is, for many reasons, painful to be close to baby. Maybe they are exhausted. It isn’t the goal of this article to judge anyone; only to present what some of the research shows so that more parents can do whatever they can with the right information.

What Is Stress for a Baby?

The difficult truth is that a baby who is left to cry, or who is not responded to with sensitivity, experiences stress, and that this stress damages the development of his brain. Right. Let’s unpick that a little. Stress. What is it? It’s a word bandied around so much that it’s lost any useful meaning so I will define it here as ‘a biochemical response to an emotional experience which is too much for your baby to manage’. Let’s remember that a baby’s is completely powerless, and his survival is dependent entirely on you. If he can’t see you, his terror is related to a fear of abandonment and death – and this isn’t overdramatic (Gerhardt, 2004, pp. 70-71). An overwhelming emotional experience can be triggered by things which would be trivial to an adult, or even to baby himself, a year down the line – such as you walking out of his sight to make a cup of tea. An end point of the biochemical stress response to this experience, which is triggered in one area of the brain, is the release of the stress hormone cortisol.

What Cortisol Does to Baby’s Brain

You’ve probably heard about this hormone in relation to adult stress, but it’s particularly damaging to a developing brain; it literally corrodes it. A baby has little or no ability to regulate his own stress, or to self-soothe; his cortisol system is highly oversensitive at birth. So long as a parent is providing a soothing environment (touch, strokes, feeding, rocking, warmth, responsiveness, smiles), his cortisol levels remain relatively low. But in the absence of these behaviours, cortisol floods his brain and corrodes the nerve tissue in brain areas needed for social interaction and socialisation as adults . It’s not difficult to see why neuroscientists and psychotherapists using this research state “the practice of regularly leaving a baby to ‘cry it out’ leaves a lot to be desired”  (Gerhardt, Corrosive Cortisol, 2004). It’s not alarmist to say that a baby who ‘cries it out’ on a regular basis is literally poisoning his own brain. It also gets worse; the presence of cortisol in the brain sensitises the tissue to cortisol exposure in the future – so the baby (and the adult, later) becomes progressively less able to self-soothe and progressively more sensitive to stress (Dettling A. , 2002). This is why I emphasise that ‘regularly’ crying it out is damaging – it’s the sustained release of cortisol which damages the brain tissue.

“If you Go to Him When He Cries, You’ll Make Him Too Needy”

In our culture, there is ambivalence about attachment concepts (Daily Mail, 2009). Many people believe that a baby who cries when he’s not hungry, or his nappy doesn’t need changing, is manipulating them and that this will lay down problems later. Well, yes – your baby IS manipulating you! He is acting in an innate, biologically determined manner which is designed to elicit those attachment and bonding behaviours from you which are essential to his brain’s development. It’s like a seagull pecking on the red spot on its’ mother’s beak to get food. Yes, he is manipulating you, but no, it isn’t bad, and no, it doesn’t lay down problems later. In fact, research shows that the more responsive a mother is in the first year of life, the less an infant will cry in the second year of his life (Bowlby, 1988). He has formed his secure attachment to you, is more confident and feels less anxious than a baby who received less responsive parenting. Now one interesting counterargument is this: babies who are left to cry may also seem to cry less. However, according to studies of cortisol production, the baby’s brain is still flooding with cortisol; he stops crying not because he is content, but because he has learned that when he cries, no one will come to soothe him (Gerhardt, Dangerous Stress, 2004). We all know people who find it difficult to express or name their emotions, and this may well be the beginning of this character trait (Gerhardt, Trying not to feel, 2004). The reason that this matters is that if emotions cannot be expressed, cortisol is released constantly in the baby (and later in the adult), which leads to suppression of the immune system and disease susceptibility. In addition, in the attempt to suppress emotions, the insecurely attached adult is likely to develop a propensity to substance abuse (Blass, 1986) (Lyons, 1996) or eating disorders (Abraham, 2008).

The Good-Enough Parent

Oh no! So does this mean that whenever I mis-read my baby, or fail to notice that he is looking to me for smiles, or when I occasionally leave him to cry because he JUST WON’T STOP, that I am stunting the development of his brain? No, it doesn’t mean that.  The concept of the ‘good enough parent’, and ‘ordinary loving behaviour’ described by psychiatrist, sociologist and psychoanalyst Donald Winnicot, is a great one to introduce here (Winnicott, 1973). Your baby needs you to fail, occasionally. It’s essential for the development of his own emotional regulation abilities, which are so important in adulthood. He needs to learn that his emotions can be soothed, and he learns this as you soothe him most of the time. But then he needs to develop an ability to do this for himself, which he can’t if you are always there, providing exquisite and ‘perfect’ parenting. In addition, it’s OK if responsive care is given by a childminder – it doesn’t have to be you all of the time (Dettling, 2002). If you are an ordinary, loving mother, you are probably doing the right thing. If you’re struggling with bonding or PND, it‘s terribly hard, but don’t waste time on guilt (there will be a reason and it’s NOT your fault)…see your GP, a family psychotherapist or a charity such as OXPIP to get some help.

There’s a lot in this article, but what you need to take home, and out, and everywhere you go, is: your responsiveness, affection and demonstrated love helps to build your baby’s brain…but so does your occasional failure!


This article was based on Susan Gerhardt’s incredible and easy-to-read book “Why Love Matters”.

(2009). Retrieved from Daily Mail:

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