Effects of N-methyl-d-aspartate receptor (NMDAr) uncompetitive antagonists in a delay discounting paradigm using a concurrent-chains procedure.

摘要: Abstract Impulsive choice is often assessed in rodents using a delay discounting (DD) paradigm which the to large reinforcer (LR) increases across session. This procedure allows one test effects of pharmacological manipulations within single Because influenced by sensitivity magnitude (SRM) and delayed reinforcement (SDR), applying quantitative analyses (e.g., fitting hyperbolic function) important for determining precise behavioral mechanisms being altered following drug administration. One caveat this approach that observing SMR/SDR can be difficult most rats choose LR when its delivery immediate, whereas some may show exclusive preference small [SR] on imposed). We utilized variant concurrent-chains (n = 8) could not either reinforcer, thus allowing observe increases/decreases responding at each delay. The NMDAr antagonists MK-801 (0, 0.003, 0.01, 0.03 mg/kg), ketamine 1.0, 5.0, 10.0 mg/kg), memantine 2.5, 7.5 mg/kg) were administered baseline training because receptor has recently been implicated DD. (0.03 mg/kg) decreased SRM SDR. Memantine (7.5 mg/kg) only. These results used study distinct aspects