Partial lesion of dopamine neurons of rat substantia nigra impairs conditioned place aversion but spares conditioned place preference.

•Rats with partial lesion of nigrostriatal dopamine failed to learn to avoid a place in which they experienced a bitter taste.•Rats with this lesion learned as well as control rats to prefer a place in which they experienced a sweet taste.•In both control and lesioned rats unconditioned responses to sweet and bitter tastes were intact and comparable.•Therefore, a sub-set of nigrostriatal dopamine neurons play a role in aversion-, but not reward-driven associative learning.