STUDY: Probiotics Affect Activity in the Brain
I spent the entirety of the 1990's working toward becoming a doctor and I was so fortunate as to come into science and medicine during a time of exponential growth in our understanding. Much of these discoveries were geared toward a better understanding of the brain. In fact, by congressional declaration in 1990, the ensuing 10 years were declared, "the decade of the brain." Since then, progress in MRI technology and PET scans measuring brain function brought all sorts of revelations.
Now, 13 years after the final sunset on the "decade of the brain," amazing things are still being discovered. Most recently - the effects of probiotics on brain activity.
The study was simple: 36 healthy women, 1/3 of which ate a yogurt containing a probiotic, 1/3 of which ate a non-fermented milk product and 1/3 eating nothing. The subjects were healthy, with no abdominal issues or psychiatric symptoms. They then underwent functional MRI scanning as they were shown images meant to stimulate anger or fear. Quite conclusively, the probiotic group showed reduced brain activity in areas of the brain involved with mood and sensation in the gut tract. Furthermore, when no stimulation was given, the probiotic group showed stronger connections between certain areas of the brain.
The study was small and limited to women, and it actually revealed very little. However, it did open a wide arena for thought and speculation. The link that they're focusing on, is of huge importance. Is it the bacteria that affects the brain? Does the bacterial activity in the gut cause the signaling? Or does the brain sense different bacterial presence in the digestive process? What are the nerve pathways between the gut and the brain? Is the affect seen on the functional MRI positive or negative when it comes to the important issues of mood and thought processing? Could probiotics potentially help treat mental disorders, depression, or pain?
We don''t know how probiotics affect the brain, but some convincing evidence has recently surfaced that shows that there is indeed a relationship. These early findings open doors for exciting advances in our understanding of the amazing brain and its response to our digestion of food by our bacteria-laden bowels.
Gastroenterology: June, 2013; 144:1394-1401.