Why Love Matters

How affection shapes a baby's brain

Sue Gerhardt

• Publisher: Routledge
• Year: 2014
• eBook ISBN: 9781317635796
• Edition: 2
• Topic: Psychology
• Subtopic: Mental Health in Psychology
• Index: Psychology

Why Love Matters explains why loving relationships are essential to brain development in the early years, and how these early interactions can have lasting consequences for future emotional and physical health. This second edition follows on from the success of the first, updating the scientific research, covering recent findings in genetics and the mind/body connection, and including a new chapter highlighting our growing understanding of the part also played by pregnancy in shaping a baby's future emotional and physical well-being.

The author focuses in particular on the wide-ranging effects of early stress on a baby or toddler's developing nervous system. When things go wrong with relationships in early life, the dependent child has to adapt; what we now know is that his or her brain adapts too. The brain's emotion and immune systems are particularly affected by early stress and can become less effective. This makes the child more vulnerable to a range of later difficulties such as depression, anti-social behaviour, addictions or anorexia, as well as physical illness.

PART 1

The foundations: babies and their brains

1

Before we meet them

When it comes, will it come without warning

Just as I’m picking my nose?

Will it knock on my door in the morning,

Or tread in the bus on my toes?

Will it come like a change in the weather?

Will its greeting be courteous or rough?

Will it alter my life altogether?

O tell me the truth about love.

W.H. Auden (1938)

The very first weeks

New life can take us by surprise. It doesn’t always follow a predictable story line of boy meets girl; they settle down, create a home and start a family. Some pregnancies happen unexpectedly after a drunken night out with a passing stranger, or with a partner you don’t even like any more. Like love, it can happen when you least expect it – or when you have been trying to have a baby for so long the thought of pregnancy has become a constant painful disappointment. Although pregnancy is easier to achieve (and sustain) in a situation of abundant nutrition and emotional well-being, in practice the scenarios are as various as people themselves.

However it does start, a biological event is triggered. Egg and sperm connect and suddenly everything is changed. The fertilised cell beds down in the nourishing wall of a woman’s womb. It rapidly grows into clusters of cells which then start to negotiate their place in the structure of the new body that is being made. Will this new tissue become a hand or a kidney or an area of the brain? It depends on where it finds itself in relation to other cell tissue. An extraordinary process begins of assembling the makings of a new human being.

Within a few weeks, the developing embryo is collaborating with the mother on a mutual construction project. Beween them, they create the placenta – which works both as an exchange hub for nutrients, oxygen and biochemical secretions (such as hormones) and as a protective barrier designed to filter out anything toxic in the mother’s system and stop it from reaching the embryo. (The placenta itself releases a substance called HCG which can make the mother more sensitive to toxins and even nauseous.) This protective system works well if the mother has a reasonably healthy lifestyle, but the placenta can find it challenging to protect the foetus if the mother is using drugs such as alcohol or nicotine.

Heavy alcohol use can cause damage at any time throughout pregnancy, but unfortunately, it has a very strong impact on the vulnerable, developing embryo during those first few weeks before it has officially become a ‘foetus’ with organs that have started to function. In these first weeks, physical structures are forming such as the shape of the face. This is when drinking ‘binges’ (defined as drinking more than six units or three or four glasses of wine at a time) especially on a regular basis can have the strongest impact, potentially leading to the distinctive facial features such as small eyes and flattened upper lip associated with Foetal Alcohol Syndrome (FAS). In an ideal world, any woman who is even half considering or risking getting pregnant would be careful not to drink too much alcohol so that this early damage can be avoided. Yet the risk continues throughout pregnancy. Even in later pregnancy, alcohol can still have serious effects on the foetal brain (RCOG 2006; Cockburn 2013). It has many different negative impacts, but it is particularly associated with smaller brains and less ability to connect right and left brain, leading to significant difficulties in learning and paying attention, as well as in empathising with and communicating well with other people (Maier and West 2001; Cockburn 2013).

The world according to mother

No foetus can flourish when it is on the receiving end of toxic chemicals. However, the foetus is also responding to a whole range of other biochemical signals from the mother. He (or she) is already actively adapting to what those signals tell him about ‘world according to mother’. Hormones, neurotransmitters and nutrients all have particular stories to tell.

What his mother eats has the biggest impact on the foetus in the first three months of pregnancy (Gluckman and Hanson 2004; Roseboom et al. 2006). The foetus needs various ingredients to develop well; in particular, sufficient protein as well as various vitamins and minerals. But he is not just relying on her nutrients for his own immediate growth. The foetus is also building up assumptions about the life ahead – as in ‘weather forecasting’, he needs to prepare for future conditions. Is it going to be a life with plentiful nutrition or one where you have to store as many calories as possible in order to survive? If the mother is undernourished or is eating junk food during early pregnancy, the foetus may reach the conclusion that there won’t be much on offer, so he develops what has been named a ‘thrifty phenotype’ designed to make the best of the resources available (Barker 1992).

Stress also has surprisingly wide-reaching effects on the developing nutritional systems of the foetus. High levels of stress hormones tend to increase the secretion of leptin, the hormone that manages appetite and food intake. They also affect the propensity of the foetus to store fat around the tummy, in the part of the body between the intestines and the abdominal wall – increasing his chances of middle-aged spread or a ‘pot belly’, which has been compared to a camel’s hump, also an effective fat storage system (Gillman et al. 2006; Entringer et al. 2012; Paternain et al. 2013). The critical window for programming this tendency to store belly fat is during mid-pregnancy, between 14 and 23 weeks (Pilgaard 2011).

Reading this research, I have been surprised at how little public discussion there has been of its implications. Poor nutrition in pregnancy may even be a major contributor to the explosion of obesity in our time. The problem arises at least in part because of the mismatch between the expectations of an undernourished foetus programmed with a predisposition to store fat, who becomes a baby and toddler unprepared for a world awash with cheap sugary and fatty fast foods and Macdonalds outlets, and rapidly puts on weight, especially round the middle (Maiorana 2007; Entringer et al. 2012). Increasingly, this is becoming a problem in developing countries such as India where 30% of babies start life underweight – but where obesity rates are dramatically increasing (Yajnik 2004; Paul 2010).

Thoughts create reality and reality creates thoughts

The mother’s quality of life is shared by her foetus. But this is not just about her physical state. The foetus also shares in her state of mind.

Once pregnant, women are prey to huge anxiety as well as huge excitement. A new role in life awaits and as in any new challenge, there may be optimism about the opportunity to develop as a person, or there may be many doubts about this transition. Hopes and fears jostle in the mind of the new mother. Will her partner cope with the baby? Will the baby’s birth be dangerous? Will she be able to meet her baby’s needs? She may feel alienated from her body as her breasts expand and her belly swells, feeling the baby is a parasite. She may feel her negative experiences are ‘wrong’.

Alternatively, there can be a strong pull to idealise the baby and herself. She hopes this is going to be the most perfect baby and she is going to be a glowing mother throughout pregnancy and beyond, who keeps her figure like the celebrities in magazines. When she finds herself groaning with nausea or compulsively eating puddings (or, in my case, egg and chips), she is disappointed with herself. Yet all these thoughts, positive and negative, are part of the mental adjustment and preparation for the new relationship that has already begun.

These extremes of idealisation or rejection can be a rollercoaster. For some women, it’s hard to strike a balance and to have confidence in the pregnancy. This is particularly true for women who are dealing with other stresses in their lives, such as a demanding job, conflicts in their relationship, or a lack of resources.

Good and bad stress

Women who are under stress may pass on their stress to their child. However, there is no easy definition of ‘stress’ in this context. Many women who do a demanding job find this a source of stimulation rather than stress; even challenging or intense relationships can be fundamentally secure and a source of strength. In any case, moderate levels of stress can be a good thing for the foetus, according to one study by Janet Di Pietro (2006). She and her colleagues in Baltimore found that mild stress or anxiety in an otherwise stable and healthy pregnancy could prompt the nervous system to mature more quickly, and could stimulate motor and cognitive development of the foetus – effects that were followed through up to the age of 2.

However, there is stress that is not helpful to the foetus. In particular, even relatively ordinary low-level stress can affect the development of emotional systems.

It is difficult to quantify this, particularly as women don’t always have an accurate perception of how stressed they are, according to Di Pietro. Some report feeling stressed yet have few biological markers of stress, while others are so used to their stressful lives (such as living in poverty or having a demanding working life) they think they are fine even when their bodies tell a different story. For most women, a job with long working hours does create a sense of strain, and during the first vulnerable months of a pregnancy, this can adversely affect the developing nervous system of the foetus, and can impair foetal growth, resulting in lower birthweights (Vrijkotte et al. 2009). This is highly undesirable, as when babies are born significantly underweight – under 5.5 pounds (2.5kg) – they face some serious health risks in later life, particularly of various diseases such as diabetes, high blood pressure or heart disease.

So while a little stress may be fine, or even beneficial in some ways, more intense or chronic forms of stress can have consequences for the baby. In particular, any situation which makes the mother feel out of control, such as domestic violence, financial anxieties or being compelled to work long hours, can over time lead to a decreased activity of the special enzyme in the placenta which normally is able to block the stress hormone cortisol from reaching the foetus (Di Pietro 2006). When this enzyme is disabled, cortisol can cross the placenta and reach the foetus, potentially affecting its developing stress response (a system I explore in more detail in future chapters). These babies exposed to their mother’s stress hormones are born more irritable and prone to crying (van der Wal et al. 2007) and are more likely to be born with more fussy ‘behavioural stress responses’ (Davis and Sandman 2007). The stress response itself can end up being reprogrammed and altered (Glover et al. 2010; Glover 2011; Oberlander et al. 2008a; Garcia Segura 2009; Sandman et al. 2011).

This may be in part due to the effects of stress hormones on the infant amygdala. The amygdala is at the epicentre of the brain’s emotional reactions and is involved in triggering the stress response itself. It is the operatic primadonna of the brain, reacting intensely to experiences of basic pain and pleasure, fear and anger, grief and joy. It is strongly connected to other important brain structures such as the hypothalamus, hippocampus and frontal cortex. In fact, it is such a core element of human life that all major amygdala structure is formed by 15 weeks of pregnancy (Buss et al. 2012).

When the developing amygdala is exposed to high levels of the stress hormone cortisol, particularly in early pregnancy,it can respond by becoming more active and growing extra connections. In fact, in some babies exposed to prenatal stress, it can increase by as much as 6 per cent in volume (Viltart and Vanbesien-Maillot 2007; Sandman and Davis 2012; Buss et al. 2012). (Strangely, this only seems to affect girl babies.)

Prenatal stress can also affect the brain in other ways. It can reduce the volume of the hippocampus (a brain structure involved in memory) and alter the size of the corpus callosum, an area in the centre of the brain connecting the right and left hemispheres of the brain (Glover 2011). Research in rats has found it also reduces connections in the prefrontal cortex (Braun et al. 2006; Murmu et al. 2006 Garcia-Segura 2009; Murgatroyd and Spengler 2011).

Late pregnancy and the brain

The last few months of pregnancy can also have a particularly strong effect on the baby’s rapidly growing brain. During this final stage of preparation for birth, the foetus is sleeping and dreaming a lot, while the neurons connect up and start to establish pathways. These pathways also start to become ‘myelinated’, coated with a slippery, fatty sheath which speeds up the nerve signalling, enabling messages to whiz along more quickly. In late pregnancy, the back of the brain is myelinated first, gradually moving across the cortex towards the frontal areas.

When a mother is very stressed during this last stage of pregnancy, her baby’s own stress response can become more reactive (Oberlander et al. 2008a). A mother who has high levels of anxiety or depression at this time is in turn more likely to have the kind of baby who finds it hard to cope with stress or new stimuli and who takes longer to get over stress (Sandman and Davis 2012). Even as a newborn, her baby may be more fearful, and is more likely to have higher than average cortisol levels at the age of 4 months (Kaplan et al. 2008). At worst, babies whose mothers are in the top 15 per cent of most anxious mothers are more likely to grow up with behavioural and emotional problems or ADHD symptoms (O’Connor et al. 2002, 2003).

Although the mother’s diet is less important in late pregnancy than it was at the start of pregnancy, there are exceptions to this. The mother’s intake of omega-3 fatty acids – found in oily fish – has an important protective effect. It seems to reduce the impact of stress and anxiety on the foetus (Hennebelle et al. 2012; Buydens-Branchey et al. 2008). The amount of omega-3 fatty acids in the mother’s blood at the time of delivery also predicts the baby’s attention span well into his or her second year (Colombo et al. 2004). Recent research suggests that choline (found in egg yolks, cauliflower and nuts, including peanut butter) may also be essential for optimum brain development at this time, particularly for the development of the hippocampus, which is also involved in managing stress as well as being responsible for some kinds of memory (Yan et al. 2013; Mehedint et al. 2010).

The unsupportive culture

In a modern, egalitarian culture where women have established their right to work on equal terms to men, attitudes to pregnancy have shifted. The gallantry of men opening doors for more fragile women is long gone. Yet pregnancy does deserve special consideration. A pregnant woman is not a woman with a medical condition but she is a new mother facing a big emotional transition as well as the demanding physiological challenge of nurturing a new human existence within her own body. She needs extra rest and she needs to know she is emotionally and financially supported. This is easy to say but hard to square with the reality of most women’s lives. Women of childbearing age are normally working full time and they and their partners may be subject to the stresses of a long working hours culture, or low pay and status.

These apparently irreconcilable realities can give rise to cynical responses like that of the journalist Catherine Bennett, who mocks the extensive precautionary advice given to pregnant women by the Royal College of Obstetricians and Gynaecologists. She believes such advice ‘infantilises’ women. As she puts it, the advice implicitly treats pregnant mothers as ‘mutinous half-wits’ because they ‘continue to work when earlier studies have proved the foetal welfare dictates maternal rest and calm. How, if not by cognitive failure, can this be explained?’ (Bennett 2013).

Obviously life is about adapting to reality. This is mostly a bumpy and uneven process of taking steps forward and steps back, of gains and losses. In our recent past, there have been major adjustments in the place of women in society. This has had huge benefits. Women have been able to create a more equal life with men, by taking advantage of the decline in heavy industry and the rise in service industries. But these positive gains have also brought unanticipated negative effects. One example is the way the fast food industry expanded as more women started to work full time. At the end of a long working day, it can be a great relief to use a ready-made meal that doesn’t demand any further effort; yet this has had an unforeseen impact on our consumption of fresh food, undermining nutritious eating habits. Similarly, having two incomes enabled many better-off families to fulfil their dream to buy their own house. However, the increased demand on a fairly static stock of housing eventually led to inflated house prices and huge mortgage debt; as a result, many women got locked in to paid employment just so they could fund their housing costs (while less well-off families got completely priced out of the market). In turn, this new economic reality contributed to the current assumption that it is a good thing for mothers to work, even during their baby’s earliest months and years when he is still dependent on his parents for continuous emotional regulation and bodily care. As a result, many parents now turn to substitute care at an ever earlier age, despite the fact that the need to keep costs down means that its quality rarely matches that of parental care. These unfolding processes affect the lives of millions of small children. Yet we keep stumbling from one unintended consequence to the next.

Although the market can and does respond to social change, when it opens up profitable commercial opportunities it is reactive and rarely promotes human needs for good care and quality nourishment unless there is strong social pressu...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Foreword by Steve Biddulph
• Acknowledgements
• Introduction to the second edition
• Part 1 The foundations: babies and their brains
• Part 2 Shaky foundations and their consequences
• Part 3 Too much information, not enough solutions: where do we go from here?
• Bibliography
• Index