Modelling drug kinetics with brain stimulation: dopamine antagonists increase self-stimulation.

The rewarding effects of brain stimulation and drugs are believed to depend on a common neural system. However, the pattern of responding produced by drug reinforcers is different from the pattern produced by conventional brain stimulation. Furthermore, pharmacological antagonists of reinforcement increase the rate of drug self-administration but depress self-stimulation. To test the hypothesis that the differences in the characteristics of brain stimulation and drugs as reinforcers are due to differences in the kinetics of drugs and brain stimulation, we modelled drug kinetics with frequency-modulated trains of brain stimulation. We report that animals will self-administer such brain stimulation in a manner that resembles drug self-administration and that, under these conditions, dopamine antagonists can increase the rate of self-stimulation.