Item recognition is associated with gut microbiota composition in healthy humans

Javiera P. Oyarzun; Thomas M. Kuntz; Xochitl C. Morgan; Emily A. Green; Lila Davachi; Curtis Huttenhower; Joseph E. LeDoux; Elizabeth A. Phelps

doi:10.1101/lm.054160.125

Item recognition is associated with gut microbiota composition in healthy humans

¹Department of Psychology, Harvard University, Cambridge, Massachusetts 02138, USA
²Department of Biostatistics, Microbiome Analysis Core, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02155, USA
³Department of Psychology, Columbia University, New York, New York 10025, USA
⁴Center for Neural Science and Department of Psychology, New York University, New York, New York 10003, USA
⁵Department of Psychiatry and Department of Child and Adolescent Psychiatry, New York University Langone Medical School, New York, New York 10016, USA
⁶Center for Brain Science, Harvard University, Cambridge, Massachusetts 02138, USA

Corresponding author: phelps{at}fas.harvard.edu

Abstract

Murine studies show that the gut microbiota—the collection of the microbes residing in the large intestine—affects memory performance in the host. However, whether commensal gut bacteria are linked to human episodic memory remains unknown. Here, we investigated whether individual differences in episodic memory performance were associated with differences in the indigenous gut microbiota composition between individuals. We show that greater gut microbiota α diversity was associated with better item recognition and that gut microbiota dissimilarity index (β diversity) between participants was associated with differences in their performance. Finally, our results suggest that Prevotella copri might play a role in the relationship between gut microbiota and human item recognition in healthy individuals. In a sample size larger than previous human studies and examining unmanipulated gut microbiota, we provide evidence that episodic memory in healthy humans is linked to their gut microbiota composition.