Competing valence-related roles of dopamine in the tail of the striatum

Understanding how the brain evaluates aversion and appetition to guide behavior remains an open question. Here, we investigated the role of dopamine signaling in the tail of the striatum (TS) in regulating competing valence-based behaviors and learning. TS dopamine dynamics were monitored as mice performed a classical conditioning task in which an odor cue predicted either an aversive air puff or a water reward. Initially, mice exhibited anticipatory blinking, which diminished over time, while anticipatory licking emerged later, coinciding with adaptation to the air puff. Dopamine responses in the TS to the air puff and its associated odor were initially elevated but declined with repeated exposure. Optogenetic disruption of this decline suppressed adaptation and hindered appetitive learning. These findings demonstrate that TS dopamine dynamics are essential for behavioral adaptation to aversive stimuli, which indirectly facilitates appetitive learning, underscoring a regulatory mechanism for shifting between defensive and reward-seeking behaviors.