Probiotic Effects on the Microbe-brain-gut Interaction and Brain Activity During Stress Tasks in Healthy Subjects

Inclusion Criteria: 1. Age: Age: 18-65 years, males/females. 2. Signed informed consent - Exclusion Criteria: 1. Concurrent or recent treatment with drugs affecting intestinal function or mood, e.g., antidepressants (\< 12 weeks) or antibiotics (\< 12 weeks). 2. Concurrent or recent (\< 4 weeks) use of nutritional supplements or herb products affecting intestinal function or mood (e.g. aloe vera, St. John´s Wort, fibers, prebiotics and probiotics). 3. Diagnosis of major psychiatric or somatic disease. 4) Abuse of alcohol or drugs. 5) Recent (\< 4 weeks) intake of proton pump inhibitors, proton pump inhibitors, PPIs (e.g., omeprazole). 6\) Asthma. 7) Cardiovascular diseases. 8) Epilepsy. 9) Renal failure. 10) Cerebral bleeding or history of cerebral bleeding. 11) Allergic to latex. 12) Pregnancy (assessed by urine test) or breastfeeding. 13) Claustrophobia. 14) Smoking or using tobacco including snuff. 15) Inability to maintain exercise routine and dietary pattern during the study. 16\) Consumption of more than 6 cups of coffee/caffeine-containing beverages per day. 17\) Professional athlete. 18) Dominant left-hand. 19) Medical implant (e.g., pacemaker). 20) Aneurysm clips in the head. 21) Shunts in the head. 22) Grenade-splinter or metal-splinter in the body (e.g., eyes). 23) Metal or electrodes in the body (e.g., temp-catheter, aorta stent, cochlea implant). 24\) Comprehensive tooth-implants or prothesis. 25) Operated in the head. 26) Operated in the heart. 27) Swallowed a video-capsule. 28) Non-corrected astigmatism. 29) Regular intake of systemic corticosteroids and anti-inflammatory medication (including NSAIDs) during the last three months. 30\) Visual defect without possibility to use lenses during MRI scanning. 31) Known allergy to milk or soy. 32) Any other reason the investigator feels the subject is not suitable for participation in the study.