The purpose of the current study was to examine the persistence, etiology, and behavioral correlates of disinhibited social behavior in postinstitutionalized children. As was expected, the children adopted from institutional care displayed more disinhibited social behavior than the nonadopted children. Surprisingly, the children adopted from foster care also demonstrated this behavior. Disinhibited social behavior was not significantly related to parent report of the degree of general deprivation encountered preadoption or to concurrent measures of general cognitive abilities, attachment-related behaviors, or basic emotion abilities. Disinhibited social behavior was associated with length of time in institutional care and with inhibitory control abilities, but the relation between disinhibited social behavior and time in institutional care appears to have been mediated by inhibitory control. The implications of these results are considered below.
Despite similar descriptions, disinhibited social behavior has been labeled variously and has been assessed using different procedures. Thus, there is concern that the different studies were describing related, but distinct, patterns of behavior. Zeanah and colleagues (2002)
found convergence of three different interviews assessing disinhibited social behavior. However, the authors emphasized the importance of a multimethod approach, as this convergence could have reflected informant bias rather than a coherent pattern of behavior. In the current study, disinhibited social behavior was assessed using an observational and parent-report measure (O'Connor et al., 1999
; Tizard & Rees, 1975
). The results from these two procedures were moderately, though significantly, related. Furthermore, the pattern of results (e.g., associations with behavioral correlates) for these procedures was generally comparable. Therefore, these results provide further evidence that the previous studies were describing a similar phenomenon.
The focus of the current study was to examine disinhibited social behavior in children internationally adopted from institutional care compared to children internationally adopted from foster care and nonadopted children. Unexpectedly, both groups of adopted children displayed more disinhibited social behavior than the nonadopted children. It has been speculated that this behavior results from the lack of a consistent, responsive caregiver rather than from general deprivation (Chisholm et al., 1995
; O'Connor et al., 1999
; Smyke et al, 2002
). In fact, it was not associated with parent report of the degree of general deprivation. Nonetheless, disinhibited social behavior in the foster care group raises questions about the etiology of the behavior, as it is believed that these children had experienced more consistent, individualized care than the children in the institutional care group. For instance, according to the parents, 75% of the children in the foster care group had been in only one foster care placement and only 5% of these children experienced some degree of emotional neglect. However, these children experienced at least one disruption in their care due to adoption. Thus, consistent caregiving might still have played a role in the development of disinhibited social behavior.
Disinhibited social behavior in both groups of adopted children might also be explained by an experience common to the international adoption process. For example, all of the adopted children experienced a major transition at adoption (e.g., new language and new routines). Additionally, the children encountered the challenge of forming an attachment relationship with their adoptive parents at a later age. Alternatively, there might be two different risk factors that contributed to the development of disinhibited social behavior in the adopted children. Perhaps the absence of a consistent, responsive caregiver led to disinhibited social behavior in the institutional care group, whereas the loss of a significant caregiver during a sensitive period led to disinhibited social behavior in the foster care group. Given the unexpected results, additional research is needed to confirm disinhibited social behavior in children adopted from foster care and to ascertain the factors involved in the development of this behavior.
To understand the underpinnings of disinhibited social behavior, the current study also examined behavioral correlates. Consistent with prior research (O'Connor et al., 1999
; O'Connor et al., 2000
), general cognitive ability was not associated with this behavior. Furthermore, the cognitive ability of the adopted children was within the average range. Thus, disinhibited social behavior does not appear to be a manifestation of a general developmental delay. As was noted above, it has been argued that disinhibited social behavior signifies the presence of an attachment disorder (O'Connor et al., 2003
). However, several results do not support this hypothesis. The adopted children did not differ from the nonadopted children in terms of attachment-related behaviors toward their parents. According to their parents, the adopted children sought out their parents in times of distress, suggesting that the children were selectively attached to their parents. Also, consistent with the research by Chisholm and colleagues (1995
), attachment-related behaviors toward the parents were not related to disinhibited social behavior. These results indicate that adopted children may display disinhibited social behavior despite having preferential relationships with their parents. Notably, in the current study, the attachment-related behaviors were based on parent report. Future research should use multimethod approaches for assessing attachment-related behaviors. Finally, although it has been suggested that disinhibited social behavior might reflect insensitivity to socioemotional cues (O'Connor et al., 1999
) and the institutional care children in the current study performed more poorly on the basic emotion abilities tasks, disinhibited social behavior was not significantly related to the ability to recognize and understand the emotional state of others.
In contrast, inhibitory control was related to disinhibited social behavior. In fact, inhibitory control mediated the relation between disinhibited social behavior and length of time in institutional care. As was proposed by MacLean (2003)
, regulatory abilities may underlie disinhibited social behavior. The children might lack the required inhibitory control abilities to regulate their behavior during interactions with unfamiliar adults despite awareness of the inappropriateness of their behavior. The current study expands upon previous studies that reported a relation between disinhibited social behavior and attention problems, as these studies relied upon parent or teacher reports for both domains (Chisholm, 1998
; O'Connor et al., 1999
; O'Connor et al., 2000
; Roy et al., 2004
). The relation between disinhibited social behavior and inhibitory control is noteworthy, as inhibitory control abilities appear to involve specific frontostriatal circuits (Casey et al., 1997
). Interestingly, previous research with postinstitutionalized children reported decreased metabolic activity in the same regions of the prefrontal cortex (Chugani et al., 2001
). Overall, these results point toward specific neural systems that may be impacted by early deprivation. Although promising, further research is necessary given that this behavior has not been described in other populations with poor regulation (e.g., children with attention-deficit/hyperactivity disorder).
Limitations of the Current Study
Several limitations of the current study should be noted. For example, the preadoption information was based on retrospective reports from adoptive parents who may not have had direct knowledge about their children's preadoption care. Their reports may have been informed by general knowledge about the quality of care provided in particular countries or by their children's functioning. In the current study, parent report of the children's preadoption experiences was not related to disinhibited social behavior. Thus, it does not appear that the parents were relying on their children's functioning in this area to inform their estimates. Nonetheless, it would be desirable to collect this information as soon as possible after adoption. Additionally, researchers could rely on more objective measures, such as time in institutional care or cognitive measures at adoption. However, with the exception of time in institutional care, disinhibited social behavior has not been related to subjective or objective measures of the quality of preadoption care (Chisholm, 1998
; O'Connor et al., 1999
; O'Connor et al., 2000
Another limitation is that the nonadopted children were advanced in terms of general cognitive ability and might not have been an ideal comparison group. The nonadopted children were raised in families that were socioeconomically comparable to the families of the adopted children. In general, children reared in affluent, enriched environments have advanced cognitive abilities (Dollaghan et al., 1999
). In fact, the children in the institutional care group were within the average range of cognitive ability despite histories of deprivation. Nevertheless, it is possible that the nonadopted children were advanced in other areas, thus overemphasizing the delays of the adopted children. Because many of the measures of interest did not have established norms, it was critical to include the nonadopted children to determine the appropriateness of the adopted children's performance. Although it is important to include comparison groups in research with adopted children, the most appropriate comparison group might vary depending upon the question of interest because each comparison group poses its own advantages and disadvantages.
Directions for Future Research
Although the adopted children were more likely than nonadopted children to demonstrate disinhibited social behavior, there was considerable heterogeneity within the groups. For example, 35% of the children adopted from institutional care and 52% of the children adopted from foster care demonstrated no characteristics of this behavior. Heterogeneous outcomes among postinstitutionalized children have been noted across multiple domains (O'Connor et al., 1999
; Rutter, Kreppner, & O'Connor, 2001
; Verhulst, Althaus, & Versluis-Den Bieman, 1990b
). That is, postinstitutionalized children are at risk for socioemotional difficulties, but these difficulties are not inevitable. In the current study, inhibitory control predicted a significant amount of the variation in disinhibited social behavior, but the complete picture remains elusive.
Thus, additional research is warranted. It will be crucial to study the development of adopted children longitudinally across multiple domains of functioning using developmentally appropriate measures. It might be helpful to focus on specific abilities with known neural substrates, such as inhibitory control. Additionally, it will be important to gain accurate, detailed information regarding the children's prenatal and preadoption care to explore the impact of specific adverse experiences. Aspects of the postadoption environment, such as parenting style and availability of resources, should also be assessed. Researchers would then be able to identify risk and protective factors in both of these environments. It is likely that gaining information about the children's preadoption experiences will remain a challenge. However, accurate information might aid in predicting the relative risk of various groups of adopted children.
More closely related to disinhibited social behavior, it might be helpful to assess the children's social behavior more broadly. For example, several parents volunteered that their children were extremely reticent with unfamiliar, and sometimes even familiar, adults. It might be beneficial to assess the complete range of behavior with unfamiliar and familiar adults, as adopted children might be more likely than nonadopted children to display extreme forms of behavior. In fact, disinhibited social behavior and extreme fear of unfamiliar adults have been described in maltreated children (Albus & Dozier, 1999
). It might also be important to assess the children's peer relationships, as parents in the current study noted difficulties in this area. Thus, there may be consistency in the children's social behavior across contexts and partners.
Finally, given the number of adopted children demonstrating persistent socioemotional difficulties, it will be important to research interventions that might ameliorate these difficulties. A number of adoptive parents expressed concern about their children's safety due to their disinhibited social behavior. Based on the results of the current study, inhibitory control abilities might be an avenue for intervention for disinhibited social behavior. However, over the years, adoptive parents seeking professional assistance for their children's behaviors have often received conflicting or ineffective advice (Gunnar et al, 2000
). Thus, it will be critical to systematically research the efficacy of the various interventions recommended for adopted children to determine the most appropriate interventions and the children or behaviors most likely to benefit from those interventions.