A positive social relationship between a child and a parent that fosters feelings of security in the presence of the parent and distress in the parent’s absence. If attachment is secure, as revealed by the strange situation test, then the child can readily separate from the primary caregiver, and actively seeks that person out on his or her return. There has been a long-standing claim that infant-caregiver patterns of attachment are largely acquired. One longitudinal study, carried out on an Hungarian sample, reported attachment disorganization was four times more frequent among children carrying at least one 7-repeat allele of the dopamine D4 receptor gene, and if classified as such at one year of age then the risk increased by a factor 10 if this gene was present together with other identifiable alleles. In a subsequent British-based twin study, however, consisting of 120 twin pairs, equated for identical and non-identical twins, levels of concordance in secure attachment to the mother did not differ between the two groups. Two other current research topics are concerned with the effects of daycare and parental separation or divorce on the development of attachment.
See Adult Attachment Interview (AAI), Allele, Attachment theory, Insecure attachment, Oxytocin, Parent-Child Interaction Theory (PCIT)< Social attachment, Strange situation test