Figure 2

Measurements of pain-like behavior by quantification of face grooming after sham or DPI surgery. a An example image showing face grooming of the mice. b–i The bar summary compares the frequency (b–e) and duration (f–i) of face grooming during the 30 min test between the sham and DPI mice. All values are expressed as mean ± SEM. n = 8–20 mice for each group shown in the figure. *P < 0.05, **P < 0.01, N.S. non-significant difference, sham vs. DPI, unpaired Student’s t test.