Specific changes in brain structure after different forms of child abuse

Scientists have found a correlation between specific forms of maltreatment and thinning of the cortex in precisely those regions of the brain that are involved in the perception or processing of the type of abuse. Credit: Fotolia 

Different forms of childhood abuse increase the risk for mental illness as well as sexual dysfunction in adulthood, but little has been known about how that happens.

An international team of researchers, including the Miller School's Charles B. Nemeroff, M.D., Ph.D., Leonard M. Miller Professor and Chair of Psychiatry and Behavioural Sciences, has discovered a neural basis for this association.

The study, published in the June 1 issue of the American Journal of Psychiatry, shows that sexually abused and emotionally mistreated children exhibit specific and differential changes in the architecture of their brain that reflect the nature of the mistreatment.

Researchers have known that victims of childhood abuse often suffer from psychiatric disorders later in life, including sexual dysfunction following sexual abuse.

The underlying mechanisms mediating this association have been poorly understood.

Charles B. Nemeroff

Charles B. Nemeroff and a group of scientific colleagues hypothesized that cortical changes during segments of mistreatment played a role.

To study these potential changes, the researchers used magnetic resonance imaging (MRI) to examine the brains of 51 adult women who were exposed to various forms of childhood abuse.

The results showed a correlation between specific forms of maltreatment and thinning of the cortex in precisely the regions of the brain that are involved in the perception or processing of the type of abuse.

Specifically, the somatosensory cortex in the area in which the female genitals are represented was significantly thinner in women who were victims of sexual abuse in their childhood.

Similarly, victims of emotional mistreatment were found to have a reduction of the thickness of the cerebral cortex in specific areas associated with self-awareness, self-evaluation and emotional regulation.

"This is one of the first studies documenting long-term alterations in specific brain areas as a consequence of child abuse and neglect," said Nemeroff, who is also Director of the Center on Aging.

"The finding that specific types of early life trauma have discrete, long lasting effects on the brain that underlie symptoms in adults is an important step in developing novel therapies to intervene to reduce the often lifelong psychiatric/psychological burden of such trauma."

Christine Heim

"Our data point to a precise association between experience-dependent neural plasticity and later health problems," said Christine Heim.

Jens C. Pruessner agreed that the "large effect and the regional specificity in the brain that corresponds to the type of abuse is remarkable."

The scientists speculate that a regional thinning of the cortex may serve as a protective mechanism, immediately shielding the child from the experience of the abuse by gating or blocking the sensory experience.

However, that thinning of the cortical sections may lay the groundwork for the development of behavioural problems in adulthood.

The results of this study extend the literature on neural plasticity and show that cortical representation fields can be smaller when certain sensory experiences are damaging or developmentally inappropriate.

Journal Reference:
Christine M. Heim, Helen S. Mayberg, Tanja Mletzko, Charles B. Nemeroff, Jens C. Pruessner. Decreased Cortical Representation of Genital Somatosensory Field After Childhood Sexual Abuse. Am J Psychiatry, June 1, 2013

Brain Structure of Infants predicts Language Skills at one year

Using a brain-imaging technique that examines the entire infant brain, researchers have found that the anatomy of certain brain areas – the hippocampus and cerebellum – can predict children's language abilities at 1 year of age. 

The University of Washington study is the first to associate these brain structures with future language skills. 

The results are published in the January issue of the journal Brain and Language.

"The brain of the baby holds an infinite number of secrets just waiting to be uncovered, and these discoveries will show us why infants learn languages like sponges, far surpassing our skills as adults," said co-author Patricia Kuhl, co-director of the UW's Institute for Learning & Brain Sciences.

Children's language skills soar after they reach their first birthdays, but little is known about how infants' early brain development seeds that path.

Identifying which brain areas are related to early language learning could provide a first glimpse of development going awry, allowing for treatments to begin earlier.

"Infancy may be the most important phase of postnatal brain development in humans," said Dilara Deniz Can, lead author and a UW postdoctoral researcher.

"Our results showing brain structures linked to later language ability in typically developing infants is a first step toward examining links to brain and behavior in young children with linguistic, psychological and social delays."

In the study, the researchers used magnetic resonance imaging to measure the brain structure of a mix of 19 boys and girls at 7 months of age.

The researchers used a measurement called voxel-based morphometry to determine the concentration of gray matter, consisting of nerve cells, and of white matter, which make up the network of connections throughout the brain.

The study is the first to relate the outcomes of this whole-brain imaging technique to predict future ability in infants.

The whole-brain approach freed the researchers from having to select a few brain regions for study ahead of time, ones scientists might have expected to be involved based on adult data.

Read the full article at: Medical Express