Lever Responses and Infusions during METH IVSA FR1 Acquisition, Self-administration, Extinction and Reinstatement.

Stable FR1 infusions averaged over 5 days of stable self-administration; extinction data averaged over the final two days of extinction. Data presented as means±SEM. Data analysed using two- or three-way RM ANOVA, followed by one-way ANOVA split by corresponding factor, where appropriate. Significant effects of ‘lever type’ are indicated by hash symbols (vs. inactive lever; ##p<.01, ###p<.001); significant effects of ‘genotype’ are indicated by asterisks (*p<.05); significant effects of ‘day’ are indicated by ‘$’ ($p<.05). Abbreviations: ALP - active lever press; FR1 - fixed ratio 1; ILP - inactive lever press.