Researchers have been able to prove that child abuse affects brain wiring of victims who have suffered it severely.
According to a study conducted with the aid of Douglas-Bell Canada Brain Bank, the researchers discovered significant changes in the neural structures in specific areas of the brains of people who suffered severe abuse as children.
For a typical brain, electrical signals used by neurons travel over long distances to communicate with cells in other regions. The longer axons of this kind are generally covered by a fatty coating called myelin.
Myelin sheaths protect the axons and help them to conduct electrical signals more efficiently. It builds up progressively- a process known as myelination- mainly during childhood, and then continue to mature until early adulthood.
According to earlier studies, significant abnormalities in the white matter- billions of myelinated nerve fibres stacked together- in the brains of people who had experienced child abuse was discovered but couldn’t be proven due to lack of brain samples.
With the recent availability of brain samples from the brain bank, the researchers compared post-mortem brain samples from three different groups of adults.
27 people who had committed suicide who suffered from depression and had a history of severe childhood abuse, 25 people with depression who had committed suicide but who had no history of being abused as children and 26 brain tissue from a third group of people who had neither psychiatric illnesses nor a history of child abuse were all put to test.
Brains of those who had suffered from child abuse were found by the researchers to have reduced thickness of the myelin coating of a significant proportion of the nerve fibres.
They also found underlying molecular alterations that selectively affect the cells that are responsible for myelin generation and maintenance.
The researchers conclude that adversity in early life may lastingly disrupt a range of brain functions.
Difficulties associated with severe childhood abuse include increased risks of psychiatric disorders such as depression, as well as high levels of impulsivity, aggressivity, anxiety, more frequent substance abuse, and suicide.