Figure 6. Frequency, scratch duration, and scratches per bout vary between neck and face scratching.

(A–G) Comparison of scratching parameters between neck and face in mice with chronic scratching behavior (n = 3 mice; n = 83 bouts for neck and 36 bouts for face). In each case, the data are plotted so that each data point corresponds to an individual scratching bout (left, pink) or an individual mouse (right, green). Parameters of interest are outlined by the gray box. p values were calculated by two-tailed, unpaired t test in each case, and ns indicates values that are not significant.

(A) Delta acceleration, representing the difference between the maximum and minimum acceleration, is similar between groups.

(B) Mean acceleration is similar between groups.

(C) Maximum speed is similar between neck and face scratching.

(D) Mean speed is slightly higher in face scratching compared with neck scratching (p = 0.0004 by bout, ns by mouse).

(E) Scratching frequency in Hertz is higher in face scratching compared with neck scratching (p < 0.0001 by bout, p = 0.0168 by mouse).

(F) Median scratch duration in milliseconds, calculated using the interpeak interval, is shorter in face scratching compared with neck scratching (p < 0.0001 by bout, 0.0428 by mouse).

(G) There are more scratches per bout in face scratching compared with neck scratching (p < 0.0001 by bout, p = 0.0335 by mouse).