Figure 3
Large ethanol bouts during the early phase of each session. (a) Drinking rate (mean bouts per 4 min) recorded during the 2-h drinking in the dark (DID) session in water (open) and ethanol (solid) mice. Shaded areas mark the early phase (5–12 min) and the late phase (112–119 min) of the session. (b) Number of bouts during the early (E) and late (L) phase for water (open) and ethanol (solid) mice. *Denotes P<0.0001. (c) Cumulative consumption over the 2-h sessions expressed as the percent of total bouts over time for control water mice (open) and ethanol mice (solid). (d) Number of bouts recorded during the first 10 min of the session for water (open, n=7 mice) and ethanol (solid, n=8 mice) mice during week 6 of DID (left) and during the following week of abstinence in which only water was available to all mice with the same DID schedule. Bars represent mean±SEM for the three combined 2 h sessions of the week. (e) Average number of ethanol bouts during the early (solid line) and late (dashed line) phase of the first, second, third, and fourth sessions of each week (the first session is the average of data from all 6 weeks; likewise for sessions two, three, and four). Gray-shaded area shows mean±SEM of the number of water bouts during combined early and late phases for the first to the fourth session of each week. *Denotes P=0.022. (f, g) Number of ethanol bouts (mean±SEM) consumed during the early (solid line) and late (dashed line) phases of the (f) 4-h session (fourth session of the week) and the (g) 2-h sessions (first, second, and third sessions of the week) over weeks 1–6. Gray-shaded area shows mean±SEM of the number of bouts for control water mice during the early and late phases combined. (h, i) BEC plotted as a function of number of ethanol bouts consumed during (h) the early phase and (i) the late phase of the 2-h session (black) and the 4-h session (gray). Dashed line is the linear fit to the data with r2=0.32 for the early phase; r2=0.0002 for the late phase.
