(A) Scratching bouts in control/Postn+/+ mice (n = 6), control/PostnlacZ/lacZ mice (n = 5), FADS/Postn+/+ mice (n = 12), and FADS/PostnlacZ/lacZ mice (n = 12) at the indicated periods after birth. (B, C) Representative traces (left) and quantitative analysis (right) of spontaneous neuronal firing (B, See also Figure S4) and correlation between scratching bouts and neuronal firing (C) in 8-week-old FADS/Postn+/+ mice (n = 5) and FADS/PostnlacZ/lacZ mice (n = 5). The data shown are the mean ± SEM of samples obtained from five (A) or seven (B, C) independent experiments. Statistical analysis was performed using a one-sided Mann-Whitney U-test (A–C); *P < 0.05, **P < 0.01. NS, not significant.