Incorporating “kawaii-ness” into your life may increase gray matter volume in the putamen and frontal gyrus

Interest in kawaii-ness is growing day by day around the world. However, the relationship between the brain and kawaii-ness remains unclear. Previous studies have revealed how adults' brains respond to infants, but there is little research into the relationship between non-infant objects that have kawaii-ness and the brain, particularly its structure. Therefore, in this study, using data from 182 healthy men and women, including 90 participants from a toy manufacturer's fan community (TMFC), we analyzed the relationship between the adoption of kawaii-ness and the gray matter volume (GMV) of region of interest (ROI). The results showed that the adoption of kawaii-ness was significantly and positively related to the GMV of the putamen, insula, frontal gyrus (FG), and rectus in the TMFC sample in an analysis that controlled for demographic data. Of these, the significant relationships between putamen and FG and adoption survived multiple comparisons. This is the first study to clarify the relationship between adoption of kawaii-ness and brain structure.