(a) Labeled mossy fibers were observed in DCN granule cell domains
(GCD) after injection of an anterograde viral tracer (AAV2-GFP) into the
ipsilateral Sp5. Scale bars: 200 μm. Right, higher
magnification views of areas indicated by dotted rectangle. Scale bars: 100
μm. White arrowheads indicate labeled mossy fibers in GCDs.
(b,c) Lick-triggered response of DCN cells before
(left) and after (right) injection of
lidocaine (b, n = 10) or saline
(c,
n
= 8) into Sp5. Thin lines are s.e.m. Solid black lines show
the RMS amplitude of the licking sound (scale bars: 1 a.u.). (d)
Lidocaine injection resulted in a significant increase in z-scored lick
responses in DCN units (P = 0.0098, Wilcoxon Signed
Rank Test, red) while no significant increases in z-scored lick
responses occurred after saline injection (P = 0.31,
Wilcoxon Signed Rank Test, purple). (e) Auditory
responses to the mimic were not significantly different in lidocaine and saline
groups (P = 0.87, Wilcoxon Rank Sum Test).
(f) Lick rate did not differ before and after injection of
lidocaine (P = 0.77, Wilcoxon Signed Rank Test) or
saline (P = 0.25, Wilcoxon Signed Rank Test).
(g) Changes in z-score lick responses were not correlated with
changes in the maximum RMS of the licking sound after lidocaine injection
(red, P = 0.36, linear regression
t-test). Changes in the maximum RMS of the licking sound did not differ between
lidocaine and saline groups (P = 0.51, Wilcoxon Rank
Sum Test).