Dips in dopamine say "no" to nicotine.

Nicotine has both rewarding and aversive effects. In this issue of Neuron, Liu et al. show that nicotine aversion depends on both desensitization of high-affinity nicotinic acetylcholine receptors (nAChRs) that activate midbrain dopamine neurons and activation of low-affinity nAChRs that inhibit dopamine neurons via the laterodorsal tegmental nucleus (LDT).