The viruses used in this article from BrainVTA are in the table below

Innate defensive responses are essential for animal survival and are conserved across species. The ventral tegmental area (VTA) plays important roles in learned appetitive and aversive behaviors, but whether it plays a role in mediating or modulating innate defensive responses is currently unknown. We report that VTA^GABA+ neurons respond to a looming stimulus. Inhibition of VTA^GABA+ neurons reduced looming-evoked defensive flight behavior, and photo-activation of these neurons resulted in defense-like flight behavior. Using viral tracing and electrophysiological recordings, we show that VTA^GABA+ neurons receive direct excitatory inputs from the superior colliculus (SC). Furthermore, we show that glutamatergic SC-VTA projections synapse onto VTA^GABA+ neurons that project to the central nucleus of the amygdala (CeA) and that the CeA is involved in mediating the defensive behavior. Our findings demonstrate that aerial threat-related visual information is relayed to VTA^GABA+ neurons mediating innate behavioral responses, suggesting a more general role of the VTA.

Figure 1. VTA^GABA+ Neurons Receive Direct Monosynaptic CaMKIIα+ Inputs from the SC

Using this looming-evoked flight-to-nest behavioral paradigm with mice, the authors found that VTA^GABA+ neurons were activated by aversive visual stimuli. Selective optogenetic inhibition and activation of VTA^GABA+ neurons showed that they were crucial for normal defense-like behavior. Tracing and electrophysiological data showed that VTA^GABA+ neurons received glutamatergic inputs from the SC and sent long projections to the central nucleus of the amygdala (CeA), which were also likely involved in the defensive behavior.