Circuits in the Ventral Medulla That Phase-Lock Motoneurons for Coordinated Sniffing and Whisking

Figure 4

Facial motoneurons and whisking. (a) ΔG-rabies injection into the mystacial pad in mice label motoneurons in the ventral lateral part of the facial nucleus, and premotor neurons (b) in the intermediate reticular formation of the medulla (vIRt). (c) vIRt cells discharge in a phase-locked manner with vibrissa motion during whisking induced by kainic acid injection in the medulla. (d) Polar plot of the coherence between spiking activity of vIRt cells and vibrissa motion at the peak frequency of whisking. Red and green dots represent protraction units and retraction units, respectively. Over 200 whisks per cell were used to compute phase angle and coherence. (e) Ibotenic acid lesion of vIRt leads to abolition of whisking on the side of the lesion (f). All panels are adapted from [19].

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