 Nicotinic receptors localize to dopaminergic cell bodies and local nicotine injections increase dopaminergic cell firing that is critical for nicotinic reward.Some additional habit-forming drugs are also likely to decrease the output of medium spiny neurons as a consequence, despite activating dopaminergic projections.For opiates, the lowest-threshold site for reward effects involves actions on GABAergic neurons in the ventral tegmental area, a secondary site of opiate-rewarding actions on medium spiny output neurons of the nucleus accumbens.