Amphibians and reptiles are born raring to go and require little parenting to get a good start in life. We humans are born in a helpless state and rely on nurturance for our early survival. Indeed, there is no species on earth that is born more helpless (altricial) than we are. It is not surprising then that attachment insecurity may trigger our disease pathways by increasing our stress.

Survival strategy

Our survival strategy is therefore locked in and plays itself out in the evolution of our brain structures and functions. Simply stated, we have a much better chance of survival when we are nested in the safety of caring parents and social group members. At a very basic level our brains will mature in a much healthier way when our upbringing matches our evolutionarily based needs with regard to basic attachment to our parents and caregivers.

As the English psychiatrist and father of Attachment Theory, John Bowlby (1907–90), said: “Our environment of evolutionary adaptedness is one of secure base attachment.”

Stress, which previously in evolutionary history related to threats to individuals and difficulty in obtaining food and sexual partners, now also became associated with threats of separation from parents or children, and from social supports. Therefore, it is not surprising that attachment insecurity may trigger our disease pathways by increasing our stress and engaging in an inflammatory response. This activation of the immune system is a remnant of the first survival challenge shared by all vertebrates - namely microbial infection. It is appropriated later when social stress becomes an issue as a defensive strategy that comes with a cost.

Frontal brain regions

Our frontal brain regions, which receive stress-laden signals from the amygdala, can reduce the outpouring of energy-depleting glutamate surges by using the brain’s most important inhibitory neurotransmitter - gamma-aminobutyric acid (GABA). Important among these frontal regions is the anterior cingulate cortex. It is here that the message of separation pain is especially felt and the decision to act to achieve an attachment solution is crafted, taking into account a bounty of cognitive and emotional information.

When you perceive yourself as once again securely attached, the anterior cingulate and other medial prefrontal cortical regions will reassure your amygdala that the threat to your attachments has been thwarted. We all face the separation challenge, and it may form the foundation for all future anxieties and fears. It was there first when we evolved our survival strategies as mammals, and it is there first when we develop individually as infant human beings. Thus, it is important to view stress and the stressors that precipitate stress using attachment theory.

Attachment anxiety

Attachment anxiety is associated with distress and leads to unhealthy reductions in heart rate variability, and increases in blood pressure, and stress hormones, and other illness vulnerabilities. Insecure childhood attachments, especially those brought on by trauma, may thus predispose to illnesses later in life. In addition, insecure attachment style may lead to the use of maladaptive behaviors, such as smoking and drinking, which are illness-provoking. Conversely, the bolstering of attachment security through social support and compassionate love may be healthful.

This experience buffers against the metabolic wear-and-tear effects of our stress and elevates our disease threshold, making it less likely we will fall ill.