Firing and Wiring: Neural Mechanisms of Long-Term Memory are Supported by BDNF via Microbiota Supplementation

Long-term memory (LTM) involves the storage of information over an extended period of time for later conscious or unconscious retrieval. Impairment of LTM occurs as a result of disrupted synaptogenesis and long-term potentiation. These neural mechanisms of LTM are regulated by the protein, brain-derived neurotrophic factor (BDNF). The presence of BDNF is dependent on the concentration of short-chain fatty acids as a result of vagal nerve communication throughout the bidirectional microbiota-gut-brain axis. Despite recent evidence in animal models and early human preclinical trials indicating probiotic and prebiotic supplementation as a viable treatment to alleviate LTM impairment, further human trials remain necessary in order to determine the efficacy of supplementation. This review addresses inconsistencies across the literature and an insufficient understanding of neuroanatomical and neurochemical responses to supplementation. The use of microbiota supplementation for the alleviation of LTM impairment may have future implications in creating accessible treatment options, along with addressing and preventing complications in patients with critical cases of COVID-19.