Childhood maltreatment associated with cerebral gray matter reductions in adolescents

"An estimated 3.7 million children are assessed for childhood maltreatment (CM) each year in the United States; because many cases do not come to professional attention, this likely is an underestimate of the number of children experiencing maltreatment," the authors write as background information in the article. "Converging data support adverse effects of early life stress on morphologic development of corticostriatal-limbic structures. Magnetic resonance imaging studies show decreased corticostriatal-limbic gray matter volume in children and adults reporting exposure to CM."

Erin E. Edmiston, B.A., then of Yale University, New Haven, Conn., now with Vanderbilt University, Nashville, Tenn., and colleagues compiled data on 42 adolescents (age range 12 to 17 years) without a psychiatric diagnosis to examine the association between exposure to childhood maltreatment and cerebral gray matter volume abnormalities. Participants were recruited from a sample of children identified at birth to be at high risk for CM, and additional participants were also recruited to allow for a sample of adolescents reporting a spectrum of CM severity. Data were collected through a self-report questionnaire, and included questions related to five subtypes of CM: physical abuse, physical neglect, emotional abuse, emotional neglect, and sexual abuse.

Self-reported scores on the Childhood Trauma Questionnaire (CTQ) were associated with a negative correlation with cerebral gray matter volume in the prefrontal cortex, striatum, amygdala, sensory association cortices and cerebellum. The authors also found that self-reported physical abuse, physical neglect and emotional neglect subtypes of CM were all associated with reductions in gray matter volume of the rostral prefrontal cortex. No significant results were found for emotional abuse or for sexual abuse.

"Although preliminary, results of exploratory analyses support prominent reductions in prefrontal cortex volume common across physical abuse, physical neglect, and emotional neglect CM subtypes, as well as patterns of additional regional gray matter volume decreases in the CM subtypes," the authors write. "Findings in girls were in regions associated with emotion regulation, whereas findings in boys were in regions subserving impulse control."

"Together, these results highlight the critical need for improved understanding of effects of childhood abuse and neglect in adolescents and of possible differences in the effects of different CM subtypes on brain development," the authors conclude. "Although adolescents with a history of CM may have symptoms and behaviors that may not yet meet criteria for psychiatric diagnoses, detection and early intervention may help improve functioning and reduce risk for the development of mood, addictive, and other psychiatric disorders."

Editorial: Conceptual and Methodological Issues in Neuroimaging Studies of the Effects of CM

In an accompanying editorial, Philip A. Fisher, Ph.D., and Jennifer H. Pfeifer, Ph.D., both of the University of Oregon, Eugene, write, "the extensive scientific literature on child maltreatment (CM) has provided strong evidence of the globally negative effects of abuse, neglect, and emotional maltreatment on healthy development and of the remarkable resilience of individuals who manage to prosper even in the face of these adverse experiences."

The authors also note that the study by Edmiston et al "broke new ground in four important ways." These include showing that cerebral gray matter volume decreases in adults and children, examining differences in gray matter according to subtypes of CM, analyzing differences in gray matter volume associated with male sex compared with female sex, and also conducting analysis of participants who do not meet criteria for a mental health disorder.

"Given the importance of the study by Edmiston et al, we believe that an expansion of research on the developmental neurobiology of CM subtypes is warranted," the authors write. "Research in these areas has great potential to address the needs for more effective prevention and treatment programs for individuals with specific CM subtypes."