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Ventral tegmental area and substantia nigra pars compacta are midbrain structures known to be involved in mediating reward.Both structures give rise to dopaminergic projections that innervate the lateral habenula (LHb), which is also known to be involved in processing painful stimuli, but its unclear what physiological effects these inputs have on habenular function.In this study we distinguished the LHb pain-activated neurons and assessed their electrophysiological responsiveness to the stimulation of the ventral tegmental area and substantia nigra pars compacta with either single-pulse stimulation (300 μA, 0.5 Hz) or tetanic stimulation (80 tA, 25 Hz).Single-pulse stimulation that was delivered to either midbrain structure triggered transient inhibition of firing of LHb pain-activated neurons.However, tetanic stimulation of the ventral tegmental area tended to evoke an elevation in neuronal firing rate.We conclude that LHb pain-activated neurons can receive diverse reward-related signals originating from midbrain dopaminergic structures, and thus participate in the regulation of the brain reward system via both positive and negative feedback mechanisms.