UC San Diego

Lateral habenula has been reported to carry the reward negative feature that distinguishes it from many other subcortical brain regions. Lateral habenula neurons are inhibited by rewarding events and activated by unpleasant events. Previous reports have revealed the role of LHb in encoding reward information. However, it is not clear how aversive stimulus affect reward processes in LHb neurons. Here we used two-photon excited fluorescence scanning microscopy to record calcium signal through GRIN lens implanted in mice with GCaMP6S expression in LHb. Based on neural responsive pattern to reward and reward omission, we categorized imaged neurons into reward-selective (RS), non-specific (NS), and non-responsive (NR) neurons. By inducing acute stress (tail shock), we observed that the reward response of RS neurons was inverted, and anticipation and consumption of reward significantly decreased. Later, we also found that the reward response in LHb neurons can be manipulated by switching between presence and absence of stress.