Working model for depressive-like phenotypes induced by LAN. IpRGCs in the retina are excited by nighttime light and subsequently activate neurons within the dorsal part of the pHb. IpRGC-recipient pHb neurons primarily project to the NAc with lower excitability during the day but higher excitability at night, thereby functioning as a “gate” to preferentially conduct light-related signals at night and release inhibitory inputs onto the NAc. Such gated ipRGCdpHb-NAc pathway is necessary for the depressive-like behaviors induced by chronic exposure to LAN.

Paper: “A Circadian Rhythm-gated Subcortical Pathway for Nighttime Light Induced Depressive-like Behaviors in Mice.”