Fig. 7.

Cumulative frequency histogram of VRC neurons from animals during interbout arousal. EtOH increases spontaneous neuronal activity in the VRC by activating a subpopulation of neurons that are silent in control conditions. A: cumulative frequency histogram of all VRC neurons with a baseline-firing rate <0.02 Hz. Spontaneous activity of neurons at baseline (black line) is nearly absent and increases progressively in response to 0.001 M EtOH (blue line), 0.01 M EtOH (green line), and 0.1 M EtOH (red line). B: EtOH differentially affects VRC neurons firing between 0.02 Hz and 0.5 Hz at baseline (black). Each of 3 doses of EtOH increases the activity of approximately one-half of these neurons and decreases the activity of the other one-half. C: VRC neurons firing >0.5 Hz at baseline (black) are progressively inhibited by increasing doses of EtOH. *Significant difference between baseline and 0.1 M EtOH.