Our study explores aspects of human conversation within the framework of evolutionary psychology, focusing on the proportion of ‘social’ to ‘non-social’ content in casual conversation. Building upon the seminal study by Dunbar et al. (1997, Human Nature, 8, 231–246), which posited that two-thirds of conversation gravitates around social matters, our findings indicate an even larger portion, approximately 85% being of a social nature. Additionally, we provide a nuanced categorisation of ‘social’ rooted in the principles of evolutionary psychology. Similarly to Dunbar et al.’s findings, our results support theories of human evolution that highlight the importance of social interactions and information exchange and the importance of the exchange of social information in human interactions across various contexts.

Mitochondrial trifunctional protein deficiency is a long-chain fatty acid disorder that may include manifestations of severe cardiomyopathy and arrhythmias. The pathophysiology for the severe presentation is unclear but is an indicator for worse outcomes. Triheptanoin, a synthetic medium chain triglyceride, has been reported to reverse cardiomyopathy in some individuals, but there is limited literature in severe cases. We describe a neonatal onset of severe disease whose clinical course was not improved despite mechanical support and triheptanoin.

It is common for philosophers to suggest that practical deliberation is normative; deliberation about what to do essentially involves employing normative concepts. This thesis—‘the Normativity Thesis’—is significant because, among other things, it supports the conclusion that normative thought is inescapable for us. In this article, I defend the Normativity Thesis against objections.

Early gut microbiome development may impact brain and behavioral development. Using a nonhuman primate model (Macaca mulatta), we investigated the association between social environments and the gut microbiome on infant neurodevelopment and cognitive function. Infant rhesus monkeys (n = 33) were either mother-peer-reared (MPR) or nursery-reared (NR). Neurodevelopmental outcomes, namely emotional responsivity, visual orientation, and motor maturity, were assessed with the Primate Neonatal Neurobehavioral Assessment (PNNA) at 14–30 days. Cognitive development was assessed through tasks evaluating infant reward association, cognitive flexibility, and impulsivity at 6–8 months. The fecal microbiome was quantified from rectal swabs via 16S rRNA sequencing. Factor analysis was used to identify “co-abundance factors” describing patterns of microbial composition. We used multiple linear regressions with AIC Model Selection and differential abundance analysis (MaAsLin2) to evaluate relationships between co-abundance factors, microbiome diversity, and neuro-/cognitive development outcomes. At 30 days of age, a gut microbiome co-abundance factor, or pattern, with high Prevotella and Lactobacillus (β = −0.88, p = 0.04, AIC Weight = 68%) and gut microbiome alpha diversity as measured by Shannon diversity (β = −1.33, p = 0.02, AIC Weight = 80%) were both negatively associated with infant emotional responsivity. At 30 days of age, being NR was also associated with lower emotional responsivity (Factor 1 model: β = −3.13, p < 0.01; Shannon diversity model: β = −3.77, p < 0.01). The infant gut microbiome, along with early-rearing environments, may shape domains of neuro-/cognitive development related to temperament.

Japanese patients often describe their pain with ideophones (sound-symbolic, imitative words), such as biribiri ‘having a continuous electric shock’. However, some manuals for healthcare workers recommend avoiding using these words in their interactions with patients, assuming that they are too subjective. We examined how reliable pain ideophones are in comparison with pain metaphors, such as denki-ga hashiru-yoona itami ‘pain like an electric current running through one’s body’. In Experiment 1, Japanese speakers rated visually presented pain ideophones and metaphors on 15 semantic-differential scales (e.g., strong–weak, momentary–continuous). It was found that the ratings of ideophones and metaphors equally varied between participants. In Experiment 2, Japanese speakers did the same rating task for a selected set of pain ideophones and metaphors presented auditorily in sentence frames. The results show that ideophones were rated more consistently than metaphors across participants, and this was true for various prosodic/morphological variants of ideophones (e.g., biriiit-to ‘having a sudden, great electric shock’, biribirit-to ‘having a momentary repetitive electric shock’). These findings indicate that ideophones can be more reliable than metaphors in health communication, especially when placed in proper context.