RecruitingDietary supplementThe Path Study: Cognitive and Inflammation Targeted Gut-brain Interventions in Alcohol; Probiotics, Alcohol, Transcutaneous Vagus Nerve Stimulation, and HIV StudyThis project uses a hybrid trial design to evaluate two biomedical interventions targeting the gut-brain axis. One intervention is portable Transcutaneous Vagus Nerve Stimulator, tVNS, that is hypothesized to stimulate the autonomic nervous system, resulting in decreased inflammation and improved cognition. The second intervention is a probiotic supplement intended to replace gut bacteria that are associated with dysbiosis in persons with HIV and alcohol consumption.