Figure 5.
In Experiment 2 pretreatment with nicotine increased approach to the lever-CS, but did not alter approach to the US receptacle. Receptacle entries during CS presentation are plotted on the left ordinate, lever contacts during CS presentation are plotted on the right ordinate. The bars represent the average number of approach responses to each location for each rat on the final three acquisition sessions (19–21). *indicates significantly more lever contacts for the PRE group, relative to the POST group, p<0.05.