RCT of foster care leads to improvements in control-related theta oscillations over one decade later

• In Event: 2-176 - Recovery from profound early psychosocial neglect 16 years after placement into institutional care

Integrative Statement

Prior work has demonstrated that children reared in institutions display a diminished capacity to monitor and control their behavior, a construct known as cognitive control. Moreover, a randomized control trial of a high-quality foster care intervention for children in institutions has been shown to mitigate deficits in cognitive control, as evidenced by behavioral performance and event-related potential (ERP) analyses of EEG data. However, two important questions remain unanswered. First, would such beneficial effects of foster care continue into the adolescent period, a time when cognitive control approaches adult levels? Second, given that theta band oscillations (4-8 Hz) are thought to reflect an organizing rhythm of the brain’s cognitive control system, would the foster care intervention alter such oscillations during performance of cognitive control tasks? For example, would the intervention restore normative increases in theta power following stimuli or events requiring control? To answer these questions, we analyzed data from the Bucharest Early Intervention Project, an ongoing longitudinal study investigating the effect of a foster care intervention on children abandoned in Romanian institutions. At approximately 21.6 months, 136 of these children were randomized to receive either a high-quality foster care intervention or remain in the institution and receive care-as-usual. At 16 years of age, the participants, now adolescents, were assessed for cognitive control ability by performing a go/nogo task while behavior and high-density EEG were recorded. Leveraging behavioral and advanced time-frequency analyses, we identified long-lasting behavioral improvements and theta band power increases for the foster care group, compare to the care-as-usual group. In particular, for events requiring control (nogo trials and error responses) the foster care group displayed significantly increased theta power relative to the care-as-usual group. When comparing the foster care group to a normative population of never-institutionalized adolescents, no significant differences in theta power emerged, suggesting that the foster care intervention was associated with typical functioning of the cognitive control system, on average. However, robust effects of the age at which children were originally placed into foster care were identified, with placement at younger ages yielding the most dramatic increases in theta band functioning during adolescence. Critically, these data present the first direct evidence of how early life experience can lead to long-lasting changes in control-related theta oscillations, providing a bridge between non-invasive studies in humans and electrophysiological studies in animal models. Collectively, these results demonstrated the benefits of a high-quality foster care intervention on the long-term health of the cognitive control system. Yet, the timing of such intervention is critical, with earlier placement into foster care yielding lasting improvements in brain activity over one decade later.

Authors

• George A Buzzell, University of Maryland, College Park
  Presenting Author

• Sonya V Troller-Renfree, Teachers College, Columbia University
  Non-Presenting Author

• Ranjan Debnath, University of Maryland, College Park
  Non-Presenting Author

• Alva Tang, University of Maryland, College Park
  Non-Presenting Author

• Charles Zeanah, Tulane University
  Non-Presenting Author

• Charles A. Nelson, Harvard Medical School
  Non-Presenting Author

• Nathan Fox, University of Maryland
  Non-Presenting Author