Noise-evoked dopamine dynamics in the nucleus accumbens and tail of the striatum

Sound is essential for threat detection. In many animals, salient sounds trigger defensive behaviors, suggesting an innate negative valence. Here, we examined how salient noise is represented in dopaminergic circuits encoding valence and saliency. In the nucleus accumbens (NAc), dopamine decreased during noise presentation in all subjects, with a subset additionally showing a transient increase at noise onset. Dopaminergic fibers from the ventral tegmental area showed corresponding patterns in the NAc. In the tail of the striatum (TS), dopamine increased in response to noise, also suggesting negative valence coding. For ramped and damped noises, dopamine dynamics are related to the temporal profile of sound intensity. Neural activity increased in both NAc and TS during noise. Together, these findings suggest that dopaminergic signaling in the NAc and TS represents noise intensity with negative valence, while NAc dopamine also reflects perceived saliency and may contribute to defensive behaviors evoked by auditory stimuli.