Road rage may originate long before a traffic incident. New research has linked serious road-related aggression to brain injury.

The findings, published Monday in the journal Accident Analysis and Prevention, indicate individuals who have experienced at least one traumatic brain injury in their lifetime report significantly higher incidents of road rage.

Such individuals are more likely to have threatened to hurt a fellow driver, passenger, or vehicle, or been involved in a motor vehicle collision that resulted in hurting themselves, passengers, or their vehicle.

"We know already that driver aggression and risk of driving collision are affected by psychiatric factors and substance use, and that this connection is strong, and we know that mental health and substance can be, both, antecedents and consequences of brain injury," said lead researcher Gabriela Ilie, M.D., a post-doctoral fellow at St. Michael's Hospital in Ontario, Canada.

"Through this study, we wanted to examine if a link between traumatic brain injuries and road-related aggression and driving collisions also exists."

A traumatic brain injury was defined as a hit to the head that resulted in loss of consciousness for at least five minutes or overnight hospitalization.

Dr. Ilie said the findings, which are based on surveys of nearly 4,000 adults, spotlight the importance of brain injury prevention, and screening and rehabilitation services for drivers who live with a traumatic brain injury.

"Perhaps the burden of traffic collisions and road rage could be mitigated if we were mindful of the implications associated with a brain injury," she suggested.