Attached
From cradle to grave, we are soothed and rocked
by attachments – our source of joy and pain, and
the essence of who we are
Photo by Jianan Yu/Reuters
Mostafa El-Kalliny is an MD/PhD trainee at the University of Colorado.
Zoe R Donaldson is an assistant professor in psychology and neuroscience and
molecular, cellular and developmental biology at the University of Colorado Boulder.
e scene is a familiar one: an urban park, with young couples picnicking, dog
owners playing fetch, parents chatting while their children scamper around. Marie –
a young child – becomes entranced by a new wonder of her world – maybe a
springtime butterfly, maybe another child throwing an impressive fit. Eventually,
looking away from her intense focus, she realises that the world has shifted around
her and that her parents are no longer in sight. Interest and elation morph into
concern and fear, as she holds back her tears and begins to search. Just around the
corner, she finds her father, who scoops her up, and, as quick as her fear started, it
dissipates; her world is complete and safe again.
From the moment we are born, we are hardwired to seek attachment to others.
roughout our lives, relationships that involve attachment serve as sources of
emotional security, joy and companionship, while at other times, pain and grief.
Compared with those of other animals, human relationships are staggeringly
multifaceted. Yet despite this, what lies at the core of our relationships is an
elaboration of a phenomenon whose roots across the species spectrum are wide and
deep. As we wend our way through life’s course – from infancy to adolescence to
adulthood to loss – attachment holds a strong grip on our lives, shifting to
accommodate our changing needs. While the roots of this phenomenon tell us much
about who we are, they tell us just as much about mysteries that remain unanswered
in evolution, psychology, neuroscience and more.
In
e Conquest of Happiness (1930), the British philosopher Bertrand Russell wrote:
ose who face life with a feeling of security are much happier than those
who face it with a feeling of insecurity … e child whose parents are fond of
him accepts their affection as a law of nature … e child from whom for
any reason parental affection is withdrawn is likely to become timid and
unadventurous, filled with fears and self-pity, and no longer able to meet the
world in a mood of gay exploration.
What Russell was describing would only later in the 1930s get a scientific description,
when the Austrian zoologist Konrad Lorenz observed that ducks and geese are hardwired to become attached to the first moving figure they encounter in their life, and
will demonstrate signs of distress if separated from that figure. Lorenz found this
innate drive to be so strong that attachment happens regardless of whether it’s to the
birds’ mother, a bicycle tire or Lorenz himself.
While it’s more complicated for human babies, in the 1950s, the British psychologist
John Bowlby extended this concept to us. He observed that children who were
separated from their families during the air raids of the Second World War first
tended to cry out in protest while seeking them out, then would lie in vigilant despair,
then become detached. Bowlby’s observations led to his principle that children, from
day one, begin to develop unique mental models of how their primary caregivers
recognise and respond to their needs. In effect, these caregivers serve as a base from
which to explore the world and, in doing so, become the first of many attachments we
experience in our lives. As Bowlby wrote:
All of us, from the cradle to the grave, are happiest when life is organised as
a series of excursions, long or short, from the secure base provided by our
attachment figures.
e importance of this secure base can hardly be understated. Imagine our park
denizens in the age of the Second World War. Kai – a child who plays at that park –
is evacuated to live in the peaceful countryside without his parents. Another park
child, Marie, remains in London, and experiences bombings and war-related events
but in the company of her parents. While perhaps not intuitive – after all, Kai’s
parents also had their child’s safety at heart – those who stayed in London with their
parents, despite the constant threats of bombings, ultimately fared better
psychologically.
But why are we – or any other species – innately driven to form attachments? As the
Ukrainian American geneticist eodosius Dobzhansky wrote in 1973: ‘Nothing in
biology makes sense except in the light of evolution.’ In infancy, attachment
behaviours such as crying likely evolved to keep caregivers nearby and attentive, so
that survival needs could be addressed. is ensures that children become adults and
pass on their genes to a new generation; survival and passing on genetic material are
ultimately the currency of evolution.
Although the attachment bond that forms between parents and children is universal,
many flavours of it exist. In 1978, the American Canadian psychologist Mary
Ainsworth described how to parse these different styles of attachment. She
developed the Strange Situation Procedure, in which she watched infants as their
caregiver left them in the room with a stranger and returned later on. By observing
the interplay between infant, caregiver and stranger, Ainsworth was able to relate
different patterns of attachment to differences in how sensitive and aware mothers
were when it came to their children’s emotional needs. If Marie – the butterflychasing child from the park – has a consistently sensitive mother, then she will also
tend to use her mother’s return to regulate her distress, before returning to
exploration without much difficulty. In contrast, Kai might have an inconsistently
sensitive mother, leading him to develop an anxious-ambivalent pattern of
attachment: a conflicted interplay between showing bursts of anger and clinging to
his caregiver when she returns. Yet another child – Pierre – might have a cold and
insensitive mother, leading him to develop an avoidant attachment style, evidenced
by a tendency to pull away when reunited, seemingly in an attempt to be self-reliant
in regulating his own distress.
Why did we evolve the capacity for different attachment styles? Why would an infant
become detached when faced with an unresponsive caregiver? We can imagine that
such caregivers, especially in the evolutionary past, might have been unresponsive
because they were busy trying to survive in a dangerous or resource-scarce
environment. A detached and self-reliant attachment style might be the best way to
try to keep this caregiver around but without overwhelming them and risking being
abandoned. In other words, even insecure attachment styles probably evolved as
context-appropriate adaptations that help children survive in the world.
e insights gained from watching infants’ reactions in the Strange Situation
Procedure remain foundational today, and it’s clear that styles of attachment – in
childhood and beyond – are intimately related to the quality of early caregiver
sensitivity. Yet just as we don’t form irreversible attachments to the first moving thing
we see, human attachment types ultimately reflect the multifaceted nature of our
experiences. People demonstrate a wide spectrum of all sorts of behaviours,
including an array of social attachment. Attachment theory alone can’t explain the
complete spectrum and, just as with the psychoanalytic frameworks that preceded it,
we shouldn’t allow it to.
Existing secure attachments can be a backbone
for absorbing and alleviating stresses from new
relationships
As we grow older, we venture away from the secure base of our parents and into
deeper relationships with peers. In 1973, Bowlby analogised this continuity of
attachment behaviour as a railway system in which a traveller leaving a city centre
becomes more and more committed to their trajectory over time. How we navigate
this trajectory reflects our attachment experiences. For instance, if Kai has already
developed an anxious style of attachment, he might tend to demand a greater
amount of intimacy and be hypersensitive to signs of responsiveness or its absence.
On the other hand, Pierre, who has developed an avoidant attachment style, will tend
to minimise intimacy or interdependence in his new relationships. Marie, who has a
secure attachment style, might have a greater ability to ignore or forgive temporary
unavailability.
Although Bowlby and Ainsworth didn’t endorse romantic or friendly relationships as
extensions of attachment behaviour, others have pointed out that, just as childhood
attachment figures play a role in providing comfort and alleviating distress, so, too,
do peers and romantic partners. is ability to distribute and buffer stress is
especially significant in adolescence, amid the turmoil of new friends, first breakups,
hormonal changes and more. It might not surprise you, then, that like Marie,
adolescents who have secure attachment styles tend to develop more positive coping
skills than their insecurely attached peers, who are more prone to a variety of
maladaptive outcomes, including symptoms of depression. In part, this might be
because existing secure attachments can be a backbone for absorbing and alleviating
stresses from new relationships. ose who come from a world of insecure
attachments don’t have the same luxury.
Altogether, early life attachments serve as training grounds for the adult bonds that
we go on to engage in. Regardless of attachment style, all of us tend to be drawn
towards the allure of falling in love and forming romantic relationships that are
hallmarked by pair bonding. Within the context of these bonds, Kai, Pierre, and
Marie’s adult attachment styles are likely to be similar to what they were in their early
lives, by turns demanding, pulling away from, or exhibiting confidence in their
respective relationships. But as with most complex behaviours, attachment styles are
not set in stone; individuals can shift towards or away from different ends of the
spectrum, especially when faced with experiences such as an unexpected infidelity or
an unusually caring partner. Although we know relatively little about the wilful
change of attachment styles, we do know that it’s possible, and that, if adults choose
to, therapy and self-knowledge can be a catalyst.
Pair bonds form the core of social monogamy, a mating system that arose
independently throughout the animal kingdom, and is found in less than 10 per cent
of mammals. (Social monogamy involves paired living arrangements between adult
males and females, versus genetic monogamy, in which adults pair-mate strictly with
each other for life.) Social monogamy had a particularly late emergence in the
primate lineage, and it remains our preferred mating system as humans. ere is no
single answer to why social monogamy has emerged over and over through the
course of evolution but, in all cases, pairing up must have provided an evolutionary
benefit. For our predecessors, this benefit might have helped in producing more
offspring but, more importantly, it might have helped to maximise the ability of those
offspring to pass on their own genes to the next generation.
In a dangerous or resource-poor environment, pair bonding might have enabled our
mammalian species – in which the presence of the mother is required for nursing –
to thrive. e ongoing presence of the father might have been essential for the
survival of offspring who might otherwise be killed by a different male aiming to end
the pause in female fertility that often accompanies breastfeeding. Other arguments
invoke mate scarcity, meaning that a male might have been better off sticking around
and waiting for a sequential mating opportunity with the same female, rather than
leaving and hoping to find another mate. And in some cases, selective pressures
might have had little to do with the surrounding physical environment, and more to
do with avoiding pathogens; a limited number of mating partners is an excellent way
to avoid passing on sexually transmitted infections.
Regardless of the specific pressures that led to pair bonding, what emerged was that
our hominin ancestors paired up to raise children together, in the setting of huntergatherer tribes in which mothers and fathers probably had equality in residential
decision-making. e presence of two caretakers enabled, for the first time,
simultaneous care for multiple dependent children, which, during our evolutionary
past, was nearly impossible for a mother to do alone. e source of this additional
care wasn’t necessarily the father, either; one counterargument is that the survival of
grandmothers well beyond their reproductively active years – a trait not seen in other
primates – was selected for because it helps to provide such care.
Attachment theory can help all families by
informing social policy
In any case, the prolonged supply of resources for children provided the time and
energy required for us to grow larger, more complex brains. e relationship between
social bonds and brain size is probably bidirectional, too, with the emergence of
more complex brains also leading to more complex social relationships. As a result,
we as a species are capable of tremendous flexibility, and employ a variety of social
organisations – polyandry, polygyny, polyamory, serial monogamy, and others –
depending on factors that include culture, religion and the distribution of resources
in society. However, what remains a universal human truth – even in societies that
don’t demonstrate pure monogamy – is that we all rely on bonds. We are unaware of
any documented culture in which humans are truly solitary creatures who raise their
offspring in isolation.
Although we can’t point to universal evolutionary reasons for specific attachment
styles, we know that their diversity and continuity should be interpreted in the
context of broader socioeconomic factors. In other words, the reason why Pierre
develops an avoidant attachment style while Marie develops a secure one goes far
beyond factors that are purely intrinsic to their parents. While many parents valiantly
provide excellent care even in the face of challenges beyond their control, there
remain very real constraints that are related to societal and economic realities. ese
constraints, which in the US include a lack of compensated parental leave, contribute
to an uphill battle in finding the time and energy to provide emotional sensitivity, and
thus secure attachment. Likewise, no parent is a blank slate, and Pierre’s parents
might themselves have come from an upbringing of insecure attachment or, even
worse, exposure to abuse or trauma. is highlights the age-old adage that ‘it takes a
village’ to raise our children; attachment theory can help all families by informing
social policy. Decades ago, Bowlby’s ideas helped to bring about a policy that we take
for granted today: that parents are routinely admitted to hospitals alongside their
children. Modern policy relating to early education, childcare and social assistance
could similarly benefit from the perspectives of attachment theory.
Our systems for thinking about attachment are notably limited, however, in their
applicability to cultures that differ from those that the US evolutionary biologist
Joseph Henrich refers to as ‘WEIRD’: Western, English-speaking, industrialised, rich
and democratic. is is especially true in an age in which pair bonds come in many
forms and are being progressively less institutionalised into marriage. Differences in
bonding preferences should remain disentangled from ethical judgment, and we
should be wary of stigmatising natural variations in behaviour. is is especially
salient given the history of practices that have harmed neurodivergent children
across the behavioural spectrum by carrying out procedures such as restraint and
forced eye contact, in the name of providing ‘attachment-based’ therapy. Even if our
science someday gives way to a capacity to medically alter the spectrum of
attachment behaviour, there will always lie the question of medicalisation and what it
means to consider oneself or someone else as disabled.
The neuroscience of attachment imparts yet another layer of richness to our
understanding. Consider a young Pierre who derives comfort from a favourite
blanket, a college-aged Marie who derives comfort from a daily run, or an adult Kai
who derives comfort from meditation or worship. In all of these scenarios, the object
of attachment provides a sense of security and reward; it’s likely that many
attachment behaviours, including social attachment and even maladaptive
attachment to drugs of abuse, recruit overlapping brain mechanisms of reward and
motivation.
We can think of these brain mechanisms as a network of circuits that carry different
streams of information, selectively sped up or slowed down by a variety of chemicals
and moulded by experience. Consider serotonin, a chemical that began to be
synthesised more than a billion years ago by unicellular organisms. Among other
things, this single chemical has gone on to facilitate the stinging mechanism of coral,
the swimming of sea urchins, and the emotional behaviour of humans. Although we
remain unable to pin down the symphony of effects orchestrated by this ancient
molecule, serotonin is integral for feelings of reward. Perturbations in the serotonin
system during early development shape individual differences in anxiety and social
behaviour. Serotonin accordingly remains the target of some of the most commonly
used pharmacological approaches for treating depression and anxiety. Other
chemicals, such as dopamine and endogenous opioids, also play crucial roles in
signalling reward. Altogether, across the lifespan, many circuits and chemicals
probably serve similar functions across a wide array of attachments.
Yet there is a neuroscience that underlies social attachment, in particular. In the
1950s, the ancient signalling molecule oxytocin was found to be a master regulator of
maternal behaviour and physiology by inducing labour and the release of milk during
lactation. ese physiological actions, however, would serve little purpose if oxytocin
didn’t also induce a strong desire in a mother to care for her young.
Attachment behaviours emerge from a sea
whose tides are being shaped by genetics,
experience and chance
Oxytocin’s role in maternal affiliation led the US neurobiologists C Sue Carter and
omas Insel to ask whether the same molecule also underlies other forms of
attachment. To test this, they turned to a small rodent found ubiquitously throughout
the central grasslands of North America, the aptly named prairie vole. Like humans
but unlike the more commonly studied laboratory rodents, prairie voles form lifelong
pair bonds, sharing a burrow and co-parenting their offspring. In 1992, Carter, Insel
and colleagues found that they could keep bonds from forming by blocking oxytocin
signalling, or could induce animals into forming a bond if they infused oxytocin. With
James Winslow, they went on to show that vasopressin, a cousin of oxytocin that
originates from the same ancestral gene and differs from oxytocin in just two
chemical locations, is equally important to pair bonding, but only in males. While
oxytocin and vasopressin critically modulate adult attachment, they do so not in a
vacuum but in concert with the other systems of the brain, which all come together in
exerting their effects on individual cells, or neurons.
We know that attachment behaviours ultimately emerge from how this sea of
chemicals affects the brain’s neurons, a sea whose tides are constantly being shaped
by a combination of genetics, experience and chance. But modern science is only
beginning to understand how this all happens, and how it plays out across life in
different regions of the brain, from neurons of the hypothalamus, a highly
multifaceted survival-focused area, to the prefrontal cortex, which carries out higherlevel computations, such as social rank. In our own work, we have often studied the
nucleus accumbens, a region that monitors motivation and orchestrates goal-directed
behaviour. We have found that neurons in the nucleus accumbens of the prairie vole
encode a representation of partners that seems to grow as pair bonds deepen over
time. We still don’t know how generalisable these processes are to human
experience. What we do know, however, suggests that such complex systems,
underpinned by oxytocin and vasopressin, translate the differences between Pierre,
Marie and Kai into their biology, shaping their present-day social behaviours. Science
is still far from deciphering the biological tapestry of human attachment and how it
plays out over time. As Bowlby himself said: ‘Here is still a continent to conquer.’
In the same park where Marie, Pierre and Kai played as children, there might very
well be a memorial bench that bears witness to what is perhaps the final
manifestation of attachment: loss. e loss of loved ones – parents, partners, siblings,
friends – are some of the most traumatic events we undergo in our lives. In her
memoir e Year of Magical inking (2005), the writer Joan Didion described the
process of bereavement as a ‘relentless succession of moments during which we …
confront the experience of meaninglessness itself’.
From an evolutionary perspective, the existence of grief has long been a puzzle: why
did we evolve this capacity to feel intense pain that can make us unable to return to
our previous lives, unable to – as Charles Darwin put it – recover our elasticity of
mind? Bowlby’s answer was that grief was not selected for on its own but was rather a
byproduct of attachment in general. In other words, our attachments manifest not
only as the sense of reward that we derive from being around those we love, but also
as the negative emotions we feel when separated from them. Bowlby observed that
the response to loss seems to parallel the protest-despair-detachment stages of being
separated from a caregiver in childhood. In the case of loss, these negative emotions
can’t be relieved through reunion, so the bereaved must instead learn to cope and
adapt.
In the novel e Stranger (1942) by Albert Camus, a man named Meursault stands
trial for murder. In the case brought against him, the prosecutor tells the jury that
Meursault seemed not to grieve even at the death of his mother, suggesting this as
more evidence of Meursault’s criminality. is argument is convincing because grief
is a universal human experience. However, we now know that, just as attachment is a
spectrum, so too is the experience of grief. Most people experience feelings of acute
grief followed by an ‘integrated’ grief in which they begin to obtain satisfaction from
life again. For many, integrated grief involves a reworking of a relationship rather
than its end; bereaved people sometimes characterise this as transitioning from
painful to bittersweet memories of their lost loved one. However, Pierre, Marie and
Kai are likely to engage in these processes in ways that partially reflect their
attachment styles, ultimately affecting how they incorporate the finality of loss into
their lives. Bowlby theorised that Pierre’s tendency to be hypersensitive to responses
from attachment figures could translate into chronic hyperactivation when faced with
loss, leading to a chronic yearning. Conversely, Kai’s avoidant attachment style could
translate into a tendency to dissociate or distance himself from thoughts of loss,
leading to failure to integrate and accept its finality. Although this theory is too
simplistic to capture the complexities of why we each grieve the way we do, there are
nevertheless meaningful associations between an avoidant attachment style and
poorer grieving outcomes.
Stoic philosophy counsels us to recognise that
our loved ones are on loan and cannot be
possessed
Perhaps reflecting these individual differences in how we engage in grieving, one in
every 10 to 20 people experience a feeling of grief that lives on and on, reflecting a
stalling of the normal recovery process. is sort of grief, which is medically known
as pathological or complicated grief disorder, can manifest as more than a year of
feeling the same degree of pain day after day, the same inability to reengage with
friends and hobbies that were previously satisfying. Although many progress through
this experience on their own, others often seek out help. Our therapies for helping
them are often effective but they’re nevertheless hindered by our limited
understanding of the psychological and neurochemical underpinnings of loss. We
know similarly little about what happens when Pierre or Marie experience the end of
attachments through rejection in adolescence or divorce in adulthood; do the
underlying processes resemble those of grief? ese sorts of questions will become
only more pressing over time, especially given the millions worldwide who are facing
or will face the loss of loved ones to the COVID-19 pandemic.
While our attachments are punctuated by the extremes of joyful reunion and painful
loss, for most of our lives, the tenor of attachment is best described as somewhere in
between. e reality is that, in all social attachment, there are undercurrents of
satisfaction and dissatisfaction that can be traced back to a variety of origins, from
the actions and inactions of partners, to matters of compatibility and an inexplicable
lack of feeling fulfilled. One view that has provided inspiration over many centuries is
that particular approaches to attachment can themselves lead to pain and suffering.
Stoic philosophy counsels that peace of mind arises from living a life in which we
minimise how affected we are by events that lie beyond our control – including
events from the social realm, and even when in love – by recognising that our loved
ones are on loan and cannot be possessed. Buddhist doctrine also advocates
nonattachment – not as a dictate to withdraw from relationships, but as a call to
engage in them while recognising the impermanence of those we engage with, just as
readily as we recognise the impermanence of our own selves. e Buddhist concept
of nonattachment has little parallel with Bowlby’s concept of secure attachment, but
has been studied on its own accord, with evidence to suggest that higher levels of
nonattachment are associated with more positive interpersonal outcomes. One
interpretation is that the self is not viewed as separate from everyone and everything
else.
ere is an unending tug-of-war in which our sciences try to distil the complexity of
the world down to fundamental principles. But it’s impossible for scientific theories
to express even a fraction of how it can feel to lose – or reunite with – someone we
cherish. ese attachments, we rightfully believe, are ours, and not reducible to a set
of scientific observations. And yet, there is nevertheless something that we can take
away from the science, and that is a call to honour the ineffability of our attachments,
knowing that they are built from processes that have evolved their way through
billions of years and live on in each of us today. While we might come away with
disgust at how a person such as Meursault could seemingly live a life without social
attachment, maybe it’s more fitting to feel pity for the life that hasn’t experienced an
attachment worth grieving for – and to treasure our own all the more.
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aeon.co
16 July 2021