The insecurely attached brain: How early social interactions can shape adult brain function

This blog post first appeared on http://thepeoplesscience.org/ on October 29, 2016.

In a first review paper within the field, Patrik Vuilleumier and I recently proposed a model describing how attachment insecurities influence social brain function in healthy adults. It has been known for more than four decades that early social interactions can crucially shape social behavior throughout the lifespan. Evidence regarding the underlying neural mechanisms, however, has only started to emerge during the last years. Because attachment insecurities have a high prevalence, can be transmitted across generations, and increase the risk for social emotional disturbances, we hope our model can help advancing new prevention and treatment approaches.

Humans are a highly social species. We enjoy the company of friends and like sharing our personal experiences with others. Mutual social interactions and self-disclosure usually entail increased activity in our brain’s reward circuit: the very same network that is activated by basic reinforcers such as food or sex. It simply feels good to be social. Conversely, when we are socially excluded, activity increases in areas of our brain that mediate physical pain responses. Social rejection really does hurt.

In some people, however, these intrinsic links between social versus antisocial behavior and brain activity appear to be malfunctioning. Furthermore, such malfunction seems to trace back to unfavorable social interactions in early life. The brains of avoidantly attached healthy adults have been found to insufficiently activate, but the brains of anxiously attached adults to excessively respond to social and antisocial cues. Yet, what does it mean to be avoidantly or anxiously attached?

Attachment theory proposes that every child is born with an innate attachment system. Its biological function is to enhance survival through proximity seeking in times of need. Although all children become attached, their attachment can be insecure. In the case of attachment avoidance, children experience repeated interactions with unresponsive attachment figures. They therefore learn to expect social rejection and fail to associate social behavior with positive feelings. In the case of attachment anxiety, children experience repeated interactions with inconsistent attachment figures. Sometimes they are comforted by others, sometimes rejected, and this in an unpredictable way. As a consequence, anxiously attached children become overly sensitive to cues of social approval and disapproval.

Attachment theory furthermore states that these negative early attachment patterns remain rather stable during the lifespan. An insecure attachment style can thus influence social behavior and associated brain function from childhood through adolescence and adulthood. In addition, evidence summarized in our review paper indicates that attachment insecurities not only affect directly attachment-related processes (e.g., parent-infant relationships), but (almost) all social interactions, even with strangers.

Roughly 40% of individuals are insecurely attached. In addition, the plot thickens that attachment insecurities can be transmitted across generations. Insecurely attached people also run a higher risk for developing psychological and psychiatric disorders. A better understanding of the neural basis of an insecure attachment style therefore is of high general interest. If we learn how to successfully prevent and treat attachment insecurities, we can proactively increase the wellbeing of future generations.

The above described review paper appeared in Frontiers of Human Neuroscience, and is freely available here:

http://www.frontiersin.org/Human_Neuroscience/10.3389/fnhum.2012.00212/full