Figure 4. Speed- and acceleration-related scratch parameters vary based on CQ dose.

(A–G) Comparison of neck scratching parameters in mice treated acutely with 1 μM or 1 mM CQ (n = 32 bouts per group, n = 8 mice in each group). In each case, the data are plotted so that each data point corresponds to an individual scratching bout (left, purple) 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 maximum and minimum acceleration, is higher in the 1 mM group compared with 1 μM CQ (p = 0.0005 by bout, p = 0.0380 by mouse).

(B) Mean acceleration is higher in the 1 mM CQ group compared with 1 μM by scratching bouts (p = 0.0003) and trends higher by mouse (p = 0.0554).

(C) Maximum speed is higher in mice treated with 1 mM CQ compared with 1 μM when looking at scratching bouts (p = 0.0016), and trends higher by mouse (p = 0.1131).

(D) Mean speed is not different between doses of CQ.

(E) Scratching frequency in Hertz does not vary between groups.

(F) Median scratch duration in milliseconds, calculated using the interpeak interval, is similar between groups.

(G) The number of scratches per bout does not vary between groups.