Fig. 3
Relationship between oxytocin-related changes in metabolite concentration and time-course change in behavioral effect of oxytocin on autistic facial expression. Oxytocin-related increase in DMG level showed significant correlations with both the decrease in autistic facial expression, indexed as log-PDFmode of neutral facial expression, from baseline to 2 weeks (a PFDR = 0.006, r =  − 0.485, N = 43) and the increase from 2 to 4 weeks (b PFDR = 0.032, r = 0.415, N = 37) in participants with autism spectrum disorder. One participant in baseline to 2 weeks and seven participants in 2 to 4 weeks were excluded because of recording failure, defocused video images, or poor facial recognition rate at least one assessment point among these. Regression lines (solid) and 95% confidence band (dashed) were fitted using simple linear regression