Figure 4.

Effects of withdrawal from extended cocaine access on cocaine choice. Abscissae: unit dose cocaine in mg/kg/injection. Ordinates (top panels): percent cocaine choice. Ordinates (bottom panels). Number of ratios completed per component. Data are shown in the left, center, and right panels for supplemental sessions with 30, 15, and 7.5 min post-injection time-outs, respectively. In each panel, baseline data are indicated by a dotted gray line, and data obtained during access to supplemental sessions are shown by a solid gray line (identical to data shown in Figure 1). All points show mean±SEM data from four monkeys collected on days 1, 4, and 7 after termination of access to supplemental sessions.