The gut-brain connection is one of the more fascinating new areas of medical research. This intriguing two-way axis has been found to have numerous unexpected effects. On one hand some studies have demonstrated how magnetic brain stimulation can alter a person's gut microbiome while other studies have shown how gut bacteria could potentially play a role in the onset of PTSD and Alzheimer's.

A new study from the University of Maryland School of Medicine has revealed another strange gut-brain connection, this time between traumatic brain injury (TBI) and intestinal damage. Researchers have previously identified an odd connection between TBI and alterations in a person's gastrointestinal tract, but this is the first study to understand this interaction in detail and to reveal the two-way nature of the process.

The study looked at mice that were subjected to TBI, and discovered that following the brain trauma, the animal's colon became more permeable. This means that bacteria can more easily move from the intestine to other areas in the body, resulting in potentially fatal scenarios such as blood poisoning.

The team also looked at how irregularities in the gut could affect inflammation in the brain after TBI. In this instance, after infecting TBI-inflicted mice with negative gut bacteria, the animal's brain inflammation was seen to worsen. This fascinating result suggests that the harmful effects of TBI can be directly influenced by gut dysfunction.

"These results indicate strong two-way interactions between the brain and the gut that may help explain the increased incidence of systemic infections after brain trauma and allow new treatment approaches," says lead researcher Alan Faden.

The study helps explain why patients suffering from TBI have been two and half times more likely to die from digestive problems than a person not afflicted by brain injury. So far, the mechanism that is causing this strange interaction is unknown, but this is strong research affirming the complexity of this two-way connection between the gut and the brain.

The study was published in the journal Brain, Behavior and Immunity.