Figure 3.

Blockade of nicotine effect with the nicotinic antagonist mecamylamine (mean ± sem) (Levin et al., 2006a). This shows a replication of the significant improvement in choice accuracy in the simple spatial discrimination in the three-chamber task caused by 100 mg/l nicotine given by immersion for 3 min ending 40 min before testing. Mecamylamine given concurrently with nicotine (200 Early) was not effective in reversing this improvement. The same mecamylamine dose given 5 min before testing (200 Late) did successfully reverse the improvement caused by nicotine given 40 min before testing, even though administration of mecamylamine alone at this point did not impair performance.