Attachment Theory - Biology of Attachment

Biology of Attachment

Attachment theory proposes that the quality of caregiving from at least the primary carer is key to attachment security or insecurity. In addition to longitudinal studies, there has been psychophysiological research on the biology of attachment. Research has begun to include behaviour genetics and temperament concepts. Generally temperament and attachment constitute separate developmental domains, but aspects of both contribute to a range of interpersonal and intrapersonal developmental outcomes. Some types of temperament may make some individuals susceptible to the stress of unpredictable or hostile relationships with caregivers in the early years. In the absence of available and responsive caregivers it appears that some children are particularly vulnerable to developing attachment disorders.

In psychophysiological research on attachment, the two main areas studied have been autonomic responses, such as heart rate or respiration, and the activity of the hypothalamic–pituitary–adrenal axis. Infants' physiological responses have been measured during the Strange Situation procedure looking at individual differences in infant temperament and the extent to which attachment acts as a moderator. There is some evidence that the quality of caregiving shapes the development of the neurological systems which regulate stress.

Another issue is the role of inherited genetic factors in shaping attachments: for example one type of polymorphism of the DRD2 dopamine receptor gene has been linked to anxious attachment and another in the 5-HT_2A serotonin receptor gene with avoidant attachment. This suggests that the influence of maternal care on attachment security is not the same for all children. One theoretical basis for this is that it makes biological sense for children to vary in their susceptibility to rearing influence.