Study: MR shows child abuse linked with gray matter loss
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| Decreases in gray matter associated with exposure to childhood maltreatment. Source: Arch Pediatr Adolesc Med. 2011;165[12]:1069-1077 |
The brain areas impacted by maltreatment may differ between boys and girls, and may depend on the type of maltreatment: abuse versus neglect and physical versus emotional.
"Here we have teenagers who may not have a diagnosable illness but still have physical evidence of maltreatment," wrote Hilary Blumberg, associate professor in the departments of psychiatry and diagnostic radiology at Yale University in New Haven, Conn. "This could help to explain their trouble with school performance or increase their vulnerability to depression and behavioral difficulties."
Researchers compiled data on 42 adolescents, ages 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 maltreatment, and additional participants were recruited to allow for a sample of adolescents reporting a spectrum of maltreatment severity. Data were collected through a self-report questionnaire, and included questions related to five subtypes of maltreatment: physical abuse, physical neglect, emotional abuse, emotional neglect and sexual abuse.
High-resolution structural MR images of the patients were obtained on a 3T imaging system and compared with data from the maltreatment questionnaire.Reduction of gray matter was seen in prefrontal areas no matter whether the adolescent had been physically abused or emotionally neglected.
The authors found that self-reported physical abuse, physical neglect and emotional neglect subtypes of maltreatment were all associated with reductions in gray matter volume of the rostral prefrontal cortex. In addition to reductions in the prefrontal cortex, self-reported scores on the Childhood Trauma Questionnaire were associated with a negative correlation with cerebral gray matter volume in the striatum, amygdala, sensory association cortices and cerebellum.
Outside of the prefrontal areas, reductions in other areas of the brain depended upon the type of maltreatment experienced. For example, emotional neglect was associated with decreases in areas that regulate emotions.
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 [childhood maltreatment] subtypes, as well as patterns of additional regional gray matter volume decreases in the [childhood maltreatment] subtypes,” wrote the authors.
The researchers also found gender differences in patterns of gray matter decreases. “Findings in girls were in regions associated with emotion regulation, whereas findings in boys were in regions subserving impulse control,” wrote the authors.
Blumberg stressed these deficits found in adolescents are likely not to be permanent.
"We have found that the brain, particularly in adolescents, shows a great deal of plasticity," she said. "It is critical to find ways to prevent maltreatment and to help the youths who have been exposed."
An estimated 3.7 million children are assessed for childhood maltreatment each year in the U.S., according to the study.
“Converging data support adverse effects of early life stress on morphologic development of corticostriatal-limbic structures,” wrote the authors. “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 [childhood maltreatment] subtypes on brain development.” The researchers added that although adolescents with a history of maltreatment may not meet criteria for psychiatric diagnoses, detection and early intervention could reduce the risk for the development of mood, addictive and other psychiatric disorders.
Evan Godt, Writer
Evan joined TriMed in 2011, writing primarily for Health Imaging. Prior to diving into medical journalism, Evan worked for the Nine Network of Public Media in St. Louis. He also has worked in public relations and education. Evan studied journalism at the University of Missouri, with an emphasis on broadcast media.