Altered Gut Microbiota Composition Is Associated with Difficulty in Explicit Emotion Regulation in Young Children.

Executive function (EF) consists of explicit emotion regulation (EER) and cognitive control (CC). Childhood EER in particular predicts mental and physical health in adulthood. Identifying factors affecting EER development has implications for lifelong physical and mental health. Gut microbiota (GM) has attracted attention as a potential biomarker for risk of physical and mental problems in adulthood. Furthermore, GM is related to brain function/structure, which plays a crucial role in emotional processing. However, little is known about how GM compositions are associated with the development of emotion regulation in early childhood. Therefore, in this study, we examined 257 children aged 3-4 to investigate links between GM and risk to EF. EF was measured using the Mother-Reported Behavior Rating Inventory of Executive Function-Preschool version. GM composition (alpha/beta diversity and genus abundance) was evaluated using 16S rRNA gene sequencing and compared between EF-risk and non-risk groups. Our results show that children with EER-risk (an index of inhibitory self-control) had a higher abundance of the genera Actinomyces and Sutterella. Although we have not established a direct link between GM and CC risk, our findings indicate that GM of preschoolers is closely associated with emotional processing and that EERrisk children have more inflammation-related bacteria.

The acute effect of moderate-intensity exercise on inhibitory control and activation of prefrontal cortex in younger and older adults.

Exercise has a significant effect on maintaining the health of inhibitory function, a fundamental cognitive ability that supports daily mental processes. While previous studies have shown that a single bout of exercise, called acute exercise, could improve inhibitory control by stimulating the prefrontal cortex (PFC) and the arousal state, few studies have focused on the differences in the effects of exercise by age. In this study, young and older adults (mean age, 22.7 ± 1.4 and 68.7 ± 5.3 years, respectively) engaged in acute moderate-intensity exercise and inhibitory control. Before and at 5 and 30 min after exercise, the participants were asked to complete the reverse Stroop task, and their arousal state and PFC activity were measured using functional near-infrared spectroscopy. The findings showed that the overall inhibitory control improved immediately after performing acute exercise and remained improved even after 30 min. Particularly, there was a difference in the arousal state and middle PFC activity between the two age groups. Especially, the young adults showed an increase in the arousal state post-exercise, while the older adults tended to show an increase in the middle PFC activity. These results suggested that the acute exercise effects on the arousal state and PFC activity may vary depending on the developmental stage, but not for inhibitory control overtime. When these findings are considered, it is important to note that the exercise impact on cognitive control remained the same throughout the generations despite the observed changes in its impact on internal states.