De todo

Solo disponible en BuenasTareas
  • Páginas : 28 (6971 palabras )
  • Descarga(s) : 0
  • Publicado : 9 de septiembre de 2012
Leer documento completo
Vista previa del texto
Variation in neural development as a result of exposure to institutionalization early in childhood
Margaret A. Sheridana,b,c, Nathan A. Foxd, Charles H. Zeanahe, Katie A. McLaughlinb,c,f, and Charles A. Nelson IIIa,b,c,1
a Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Boston Children’s Hospital, Boston, MA 02115; bDepartment of Pediatrics, Harvard Medical School,Boston, MA 02115; cCenter for the Developing Child, Harvard University, Cambridge, MA 02138; dDepartment of Human Development, University of Maryland, College Park, MD 20742; eDepartment of Child and Adolescent Psychiatry, Tulane Medical School, Tulane University, New Orleans, LA 70118; and fDivision of General Pediatrics, Boston Children’s Hospital, Boston, MA 02139

Edited* by Bruce S.McEwen, The Rockefeller University, New York, NY, and approved June 21, 2012 (received for review January 4, 2012)

We used structural MRI and EEG to examine brain structure and function in typically developing children in Romania (n = 20), children exposed to institutional rearing (n = 29), and children previously exposed to institutional rearing but then randomized to a high-quality foster careintervention (n = 25). In so doing, we provide a unique evaluation of whether placement in an improved environment mitigates the effects of institutional rearing on neural structure, using data from the only existing randomized controlled trial of foster care for institutionalized children. Children enrolled in the Bucharest Early Intervention Project underwent a T1-weighted MRI protocol. Childrenwith histories of institutional rearing had significantly smaller cortical gray matter volume than never-institutionalized children. Cortical white matter was no different for children placed in foster care than never-institutionalized children but was significantly smaller for children not randomized to foster care. We were also able to explain previously reported reductions in EEG α-power amonginstitutionally reared children compared with children raised in families using these MRI data. As hypothesized, the association between institutionalization and EEG α-power was partially mediated by cortical white matter volume for children not randomized to foster care. The increase in white matter among children randomized to an improved rearing environment relative to children who remained ininstitutional care suggests the potential for developmental “catch up” in white matter growth, even following extreme environmental deprivation.
neglect brain development experience

|

| early adversity | brain volume | early

common societal response to orphaned or abandoned children is to rear such children in institutions (1, 2). UNICEF estimates that there are at least 8 millionchildren who live in institutional settings. Institutional rearing of young children represents a severe form of early psychological and physical neglect, and as such, serves as a model system for understanding how early experience—or the lack of thereof—impacts brain and behavioral development. In most forms of institutional rearing, the ratio of caregiversto-children is low (e.g., in our sample∼1:12), care is highly regimented, and caregiver investment in children is low (3). Children raised in institutions are more likely than children raised in families to have deficits in cognitive function (4, 5) and in language production and comprehension (6, 7). Relative to noninstitutionalized children, children reared in institutional settings experience a wide range of developmental problemsincluding markedly elevated rates of attention-deficit/hyperactivity disorder and other forms of psychopathology (8–10) and difficulties with social functioning (11–13). These developmental difficulties are not unique among children exposed to institutionalization. Indeed, exposure to a wide range of adverse early environments—including physical and sexual abuse, neglect, domestic violence, and chronic...
tracking img