Initially during acquisition of alcohol SA (FR1‐3), we observed an SDPS‐induced increase in responding during time‐out periods, in which reward delivery was omitted (Figure S2, Table S6). This effect was predominantly observed in the SDPS‐prone and, to a lesser extent, in the SDPS‐resilient groups. To further dissect alcohol‐seeking behavior during alcohol unavailability periods, we introduced a 30‐second time‐out interval following each reward, in re‐FR1 sessions 4 to 7 (Figure 4A). Analysis of active responses showed no training effect, repeated measures ANOVA: F reFR1(1.77, 56.73) = 1.56, P = 0.220, and no training × group interaction, F reFR1 × GROUP(3.55, 56.73) = 0.35, P = 0.824), suggesting that overall responding for alcohol was not affected by the change in the duration of the time‐out period (Figure 4B, Figure S3). Notably, a significant group effect was observed, F GROUP(2, 32) = 3.65, P = 0.037, because of increased responding in the SDPS‐prone group when compared with controls (P = 0.013) and a trend vs SDPS‐resilient (P = 0.061) rats. No group difference was detected between SDPS‐resilient animals and controls (P = 0.617).
