migrating interneurons also express D1 and D2 dopamine receptors, which are known to have opposite effects from one another. D1 nulls posses decerased ability to migrate, allowing the conclusion that D1 normally functions to promote cortical interneuron migration . on the other hand, d2 knockoutss posses increased migratory capability. sugesting that its tole is to inihibit migration of interneurons.