Traumatic head injuries (TBI) and Mental Disorders

It has been long known that there is a relationship between the head injuries and symptoms of the mental disorders such as changes in mood, personality, and behavior. Recent studies in this area have proven this hypothesis to be true. The studies revealed that there is a strong correlation between the TBI and various mental disorders such as schizophrenia, depression, bipolar disorder, organic mental disorders. The potential risk of developing certain mental disorders increases up to 439 percent with the individuals having a history of traumatic brain injuries.

·    In the first year after suffering head trauma, the risk of developing a mental disorder is the highest, but even after 15 years, there was a significantly increased risk. Also, there is significantly a higher occurrence of mental disorder and suicidal attempts among the individuals having TBI in comparison to those with no head injuries and have a poorer quality of life.  

Evidence for a biologic gradient

• There is not definite biological evidence are present to this association, however, there are several explanations to believe:
• TBI can destroy a region of the brain which can allow the advancement of a mental disorder related to that region
• Head injury ordinarily causes inflammation within the brain which leads to different psychological symptoms.
• A more diffuse harm such as a concussion can influence the neurotransmitters that the brain uses to communicate, resulting in the disturbed balance and this increases the chance of mental symptoms.

 Which came first: the disorder or the head trauma?

The possible outcomes of all mental disorders are well known, for instance, depression causes the lack of concentration, and during the manic phase, an individual feel much energetic and excited, becoming prone to the susceptibility to accidents. This is just like a chicken-and-egg situation.

Many Researchers have failed to address this, but Orlovska, a Danish Scientist in 2014 had tried to work around the problem. She found that people with a broken toe or similar injuries also have a higher risk of having the mental disorder, however here the risk is minimal (16-percent) as that with head injuries (65 percent). She found that disorders such as depression, schizophrenia, and the organic mental disorders are more likely to develop after suffering TBI.

Future Studies  

Knowing the fact that TBI increases the risk of developing mental disorders, it may help doctors to detect the disorder at an early stage of development. Future studies may lead to better understanding of this relationship, focusing on the severity of head injuries and the close association of TBI and mental illness.