Giesbrecht, GeraldZinman, Julia2023-10-202023-10-202023-10-17Zinman, J. (2023). The role of the autonomic nervous system in mediating the relationship between the gut microbiota and social behaviour (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.https://hdl.handle.net/1880/117423https://doi.org/10.11575/PRISM/42266Social competence is profoundly important for child development by influencing personality and quality of life. Recent discoveries indicate that bacteria within the gastrointestinal tract (i.e. gut microbiota), play an important role in social behaviour through connections to the brain (i.e. the microbiota-gut-brain axis). One of these connections occurs through the vagus nerve, which is a prominent member of the parasympathetic nervous system (PNS). We aimed to determine whether the gut microbiota at 3-4 years of age was associated with social behaviour deficits, and whether this relationship was mediated by vagal activity. We used data (n=248) from the prospective APrON study. Stool microbiota was assessed for its bacterial composition using 16s sequencing and its metabolome using liquid chromatography–mass spectrometry. Vagal activity was indexed by respiratory sinus arrhythmia (RSA) collected in lab. Social behaviour was assessed using the Behavioural Assessment System for Children (BASC-2). We used raw and adjusted Spearman correlation analyses to investigate the associations between the gut microbiota, baseline RSA and social behaviour. We investigated whether vagal activity mediates the relationship between the gut microbiota and social behaviour using PROCESS. Greater alpha diversity predicted lower Withdrawal scores at 3-4 years old. Associations between stool taxa and social behaviour were not statistically significant after performing a false detection rate (FDR) correction. Baseline RSA was positively associated with Bullying scores in males but not females. There was no significant mediation effect of baseline RSA on the relationship between the gut microbiota and social behaviour. Ultimately, exploring the intricate relationship between gut microbiota and behaviour in children is of utmost significance, as it holds the potential to revolutionize our understanding of child development and well-being.enUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.vagus nervechildhoodsocial behaviourgut microbiotaPsychology--DevelopmentalPsychobiologymaster thesis