Parents and infants: determinants of attachment in a ... - Generation R

Chapter 1
recent studies have addressed the role of biological factors such as genetics
in explaining disorganized attachment (for a review, see Bakermans-
Kranenburg & Van IJzendoorn, 2007). Little is known about the neurobiology
of infant attachment. The largest study to date investigating possible
(neuro-) biological antecedents such as maternal medical history, infant
anomalies at birth or neonatal behavioral orientation response, found no
relation of these proxies of the child’s neuro-biological status and later
attachment disorganization (Carlson, 1998; Sroufe, Egeland, Carlson, &
Collins, 2005). However, other studies found that the behavioral orientation
response of newborns predicted later attachment disorganization (Spangler,
Fremmer-Bombik, & Grossmann, 1996). Also the risk of attachment disorganization
was higher in infants with neuro-developmental problems, such as
autism, Down’s syndrome, and neurological abnormalities due to maternal
alcohol abuse during pregnancy, or premature birth (for a meta-analysis see
Van IJzendoorn et al., 1999). These findings suggest that neurobiological
factors may be involved in the etiology of attachment disorganization, but
studies addressing the role of neurobiological differences for attachment
quality in human infants are scarce.
The current study
Attachment in Generation R
Attachment insecurity and disorganization are risk factors for later socioemotional
problems. Yet, they are frequent even in general population
samples as shown by findings from the National Institute of Child Health
and Human Development (NICHD) Early Child Care Research Network
(ECCRN). The normative distribution derived by a meta-analysis including
920 non-US Western infant-parent dyads from the general population is:
51% secure (B), 20.2% insecure-avoidant (A), 10.3% insecure-resistant and
18.5% disorganized (D) (Van IJzendoorn et al., 1999). However, most studies
have been conducted with either high risk samples with multiple problems
or relatively small convenience samples. Findings from these studies may
not be easily applicable to the general population and the large group of
families who are not at high risk nor struggling with clinical problems.
In the current series of studies, we therefore examined environmental
and biological factors that may help explain individual differences in infant
attachment quality in the general population (for an overview see Figure 1).
We conducted the Strange Situation Procedure with 881 infant-parent dyads
participating in the Generation R Study when the child was 14 months old.
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