Figure 8.

Activation of muscarinic cholinergic receptors in the full model potentiates GC excitability with little impact on MC firing rates. A, Raster plot of MC spiking activity immediately before and after the onset of odor presentation, under control conditions. B, As in A, but with mAChR neuromodulation active. C, Raster plot of GC spiking activity under control conditions. D, As in C, but with muscarinic cholinergic neuromodulation active. E, Histograms of activity in all 25 glomeruli under control conditions, arranged according to their levels of afferent activation for ease of visualization. Top, Steady-state OSN input levels; middle, odor-evoked spike rates in MCs; bottom, odor-coding spike rates in MCs (see Materials and Methods). F, As in E, but with muscarinic cholinergic neuromodulation active.