This blog post first appeared on www.huffingtonpost.com on October 16, 2013, and has since been edited.
In one of my previous blog posts on human social brain evolution, I already briefly mentioned the concept of attachment and individual differences in attachment orientation. Here, I would like to elaborate on these considerations by describing in more detail what we have learned about the neural mechanisms underlying attachment behaviours in humans, and how such information could help us maintain better relationships with others.
In the late 1960s and early 1970s, Mary Ainsworth and John Bowlby first described an overarching psychology framework related to social interactions that has since become known as attachment theory. It states that, in order to survive, infants need to form a strong bond to their primary caregiver(s); they become attached. As infants grow older, this attachment evolves from a primarily biologically driven “survival instinct” into a sophisticated “cognitive-emotional social relationship processor.” A person’s mode of attachment, also called attachment style, determines what they will expect from social interactions, and how they will use cognitive and emotional resources for self-regulation during times of social and emotional challenge.
Central to the understanding of the concept of attachment is the assumption that (almost) all infants will become attached, but that such attachment can be either secure or insecure. A lot depends on how the primary caregiver(s) respond to the infant’s attempts to establish a close social connection. Ideally, the caregiver(s) are available, responsive, and caring in times of need. Infants consequently learn to trust in others and their own social emotional abilities; they can establish a secure attachment style. Unfortunately, such scenario does not always happen, leading for the formation of an insecure attachment style in infants. If the primary caregiver(s) react in an unpredictable or inconsistent manner to the infant’s social approach signals, an anxious attachment style is bound to emerge. The latter is characterized by an increased fear of abandonment and need for reconfirmation due to lower self-esteem. In turn, if the primary caregiver(s) is/are unavailable or unresponsive in times of need, infants will develop an avoidant attachment style. They learn to predict and expect social rejection and to less readily associate social interactions with positive and rewarding experiences. Interacting with others may even be seen as futile or dangerous. Consequences are social-emotional closure and sometimes even a denial for the need of social relationships.
Although the foundations of a person’s (secure versus insecure) attachment style are laid early in life, this process can have a lasting influence on social emotional abilities and well-being throughout the lifespan, and even affect future generations. This comes from the fact that an individual’s attachment style is thought to remain rather stable from childhood to adolescence and adulthood (although it can, and does, change), and may be transmitted from one generation to the next. Given that at least one third of people are believed to have an insecure attachment style and attachment insecurity is a known risk factor for the emergence of mental health problems (e.g., social anxiety disorder, or borderline personality disorder), attachment insecurity should be given appropriate consideration.
In order to develop new detection, prevention and intervention strategies for social emotional difficulties associated with attachment insecurity, researchers have recently begun to investigate the neural basis of attachment in humans. The main goal of such approach is to find neural markers of attachment insecurity in the human brain, allowing for understanding what may motivate people to react with avoidance or anxiety to social emotional signals. Because it is easiest to establish such brain-behavior associations in adults, initial research has focused on adult populations.
Let’s first consider attachment anxiety. Converging evidence from adults suggest that this insecure attachment style is characterized by hyper-sensitivity to social emotional information in general, particularly so if negative. Anxiously attached individuals show increased activity in brain areas that normally process social rejection and conflict, as well as maintain higher arousal and more negative emotionality. It looks as if anxiously attached people’s brains are locked in a constant high alert state, monitoring the environment for potential signs of social emotional threats. Even if there are none.
Attachment avoidance, in turn, seems to considerably lower the brain’s responsiveness to social emotional information, especially so if positive. Avoidantly attached individuals show lower activity in brain areas that usually process reward and prosocial motivation. This even appears to hold true for mothers seeing pictures of their own smiling infants, normally representing very potent inducers of reward-related social brain activity. It appears as if avoidantly attached individuals do not feel as good when interacting with others. Even if these interactions are mutual.
Although admittedly reductionist (for more details, see here and for a more recent account here), the above simplified description of the neural basis of attachment anxiety and avoidance nicely illustrates the influence the environment within which a person grows up can have on social emotional brain responses during adulthood. These findings in humans furthermore nicely accord with data from animal studies (see here and here), the latter suggesting that such environmental effects can even override potential genetic predispositions for attachment insecurity by means of epigenetic modifications.
The practical implications of the above-mentioned brain activation patterns associated with attachment anxiety and avoidance are manifold. Firstly, we should be acutely aware of the fact that our behavior towards infants (and all other social interaction partners, in fact) can crucially influence their social emotional brain development, shaping who they themselves will become during adulthood. Key elements of such awareness should be the maintenance of a stable, predictable, and responsive environment within which children grow up. Second, and associated with the first point, we should be more aware of our own attachment style to better understand our own reactions in the course of social interactions. This can help us to proactively change our social emotional behavior, or at least disengage from interactions early enough to prevent damage. And third, knowing more about the brain basis of attachment anxiety and avoidance, but also attachment security, we can start developing new prevention and intervention strategies specifically targeting affected social emotional reward and threat behaviours and underlying brain circuits.
Ongoing research on the neural basis of attachment insecurity in adolescents and children will hopefully soon add more information, allowing for an early detection and prevention of, and/or intervention in the case of social emotional problems associated with attachment insecurity. The sooner we can act, the better.
More information on the social neuroscience of human attachment is available here.