Cognitive enhancement of healthy young adults with hyperbaric oxygen: A preliminary resting-state fMRI study

•Hyperbaric oxygen (HBO) caused increases in spatial working memory and memory quotient.•The alternation of regional homogeneity (ReHo) induced by HBO is related to the cognitive performance.•HBO administration affects the functional connectivity of several subcortical regions.

ObjectiveTo date, no study has examined the effect of hyperbaric oxygen (HBO) on the cognitive performance and spontaneous brain activity in healthy adults using resting-state functional magnetic resonance imaging (rsfMRI). Our aim was to reveal the neural mechanism underlying the change in cognitive performance caused by increased oxygen.MethodsIn this study, we acquired fMRI data from 20 healthy young adults and used placebo-controlled (PBO) rsfMRI to identify the effect of HBO on the cognitive measures and the regional homogeneity (ReHo) in healthy adults.ResultsCompared to the PBO group, the HBO group showed the following: (1) the scores of the spatial working memory and memory quotient were significantly increased after HBO administration; (2) the ReHo value was significantly increased in three clusters, the left hippocampus, right inferior frontal, and lingual gyri, and for these three clusters, their functional connectivity with the subcortical brain system was significantly increased after HBO administration; and (3) the changes of ReHo values in these clusters generated by HBO administration were correlated with several aspects of cognitive performance, clarifying the cognitive locus of the effect.ConclusionOur results suggested that the increased availability of oxygen can, to some extent, improve memory performance.SignificantOur findings may improve our understanding of the role of HBO in clinical and practical applications.