Scientists from Baylor College of Medicine and the Texas Children’s Hospital’s Institute for Biomedical Research have identified a mechanism of direct communication between the gut and the brain that works instantly.

The study demonstrated that the body has a special neuronal pathway that recognizes certain bacterial proteins and immediately transmits information to the brain.

The key role in this process belongs to the TLR5 receptor, located on vagus nerve neurons. It is sensitive to flagellin, a protein component of bacterial flagella, Planet Today reports. Signals from these neurons reach the brain literally within seconds, bypassing the hormonal and immune systems, which ensures an instant sensory response.

Experiments were conducted both on rodents and on cell cultures. Researchers were able to track the stimulation of neurons with the TLR5 receptor and their reaction. After contact with flagellin, an almost instantaneous transmission of excitation was observed, confirming the existence of a rapid communication channel between the gut microbiota and the central nervous system.

The authors of the study note that the discovered process could change diagnostic methods and approaches to treating a number of conditions, such as depression, inflammatory bowel diseases, eating disorders, and manifestations of autism.

The revealed direct interaction between the gut microbiota and the brain also suggests the need to reconsider the number of human senses.