Fig. 2.

Representative single cocaine dose reinstatement sessions from the same rat showing each non-contingent single cocaine dose administered. Cumulative number of lever presses on the active lever (A) that occurred after completion of the injection until lever pressing stopped, and corresponding calculated cocaine levels (B) are shown. Each symbol represents a lever press and the descending curves in B represent calculated cocaine level over time for each cocaine dose. The upper and lower dotted horizontal lines represent the approximate cocaine level at the onset and cessation of lever pressing behavior respectively. 2, 3, 4, 6, 8, and 12 μmol/kg is equivalent to 0.7, 1.0, 1.4, 2.0, 2.7, and 4.1 mg/kg cocaine HCl respectively.