A circuit in the brain that changes in those who have suffered childhood trauma connects aggressive behavior towards others and harmful behavior towards oneself.
Aggression and self-injurious behavior are often linked, and it is not uncommon for them to co-occur in people with a history of childhood trauma. The association between these two aspects of behavior has long been known in the clinical field, but how are the two things connected in the brain? Research published in Science Advances has now identified the brain circuit that connects these two behaviors – a pathway that is profoundly changed after trauma.
The research could have therapeutic and social relevance, given that both behaviors are an important cause for concern for the repercussions they have on the individual and society.
Brain out of balance
By studying the brains of mice, scientists from the Center for Neurobiology Research at Virginia Tech (United States) have discovered that trauma at an early age makes neurons along the brain pathway that connects the nucleus reuniens (a primitive region of the brain important for fear regulation mechanisms) to the hippocampus, a fundamental structure for memory and learning, hyperactive.
Trauma alters the molecular properties of the brain and overexcites a specific calcium channel, which allows neurons to exchange nerve signals and therefore regulates their transmission capacity. When these neurons are overactive, the risk of aggression and self-harm behavior increases.
Pain that numbs
According to the authors of the study, pain (physical, but also emotional) can act as a gateway for the emergence of these aggressive behaviors, towards others or towards oneself, once the neural circuit underlying them is dysregulated in the brain. Ultimately therefore, there would not only be anxiety and depression at the basis of these sensational gestures, but also deep neurobiological wounds, made more evident by the brain’s difficulty in reprocessing the pain.
Improve therapies
The study adds to the many other evidence on how a difficult childhood experience can have a lasting impact not only on the psyche, but also on the biology and neural structure of the brain of those exposed to trauma. The hope is that the discovery will contribute to developing more effective therapies to prevent aggressive and self-harming behavior in people most at risk.
