Probiotics have been shown to alter brain activity as monitored by functional MRI. - GreenMedInfo Summary
Brain-gut-microbiota axis and mental health.
Psychosom Med. 2017 Aug 11. Epub 2017 Aug 11. PMID: 28806201
Timothy G Dinan
OBJECTIVE: The brain-gut-microbiota axis has been put forward as a new paradigm in neuroscience, which may be of relevance to mental illness. The mechanisms of signal transmission in the brain-gut-microbiota axis are complex and involve bidirectional communications which enables gut microbes to communicate with the brain, and the brain to communicate with the microbes. This review assesses the potential usefulness and limitations of the paradigm.
METHODS: A selective literature review was conducted to evaluate the current knowledge in clinical and pre-clinical brain-gut-microbiota interactions as related to psychiatric disorders.
RESULTS: The overwhelming majority of published studies in the field are preclinical and there is so far a lack of clinical studies. Preliminary studies in psychiatric populations, support the view of a dysbiosis in some conditions, but studies are often small-scale and marred by potential confounding variables. Preclinical studies support the view that psychobiotics ('bacteria which when ingested in adequate amounts have a positive mental health benefit') might be of use in treating some patients with mental health difficulties. To date we have no well conducted studies in clinical populations, though there are some studies in healthy volunteers. A cocktail of probiotics has been shown to alter brain activity as monitored by functional MRI and Bifidobacterium longum was reported to alter brain electrical activity.
CONCLUSION: It has yet to be convincingly demonstrated that the exciting findings of psychobiotic efficacy demonstrated in preclinical models of psychiatric illness will translate to patients.