Zona Incerta: An Integrative Node for Global Behavioral Modulation

Zona incerta (ZI) can integrate multisensory inputs. Convergence of multimodal information occurs at the level of single ZI neurons. Via different neuronal subpopulations, ZI can promote eating, hunting, and sleep, as well as bidirectionally modulate defensive behaviors. ZI encodes positive valence and promotes reinforcement of appetitive behaviors, suggesting its role in conveying motivational drive. ZI is also involved in various types of neuroplasticity, including fear learning and extinction as well as chronic pain regulation. In view of these findings, we propose that ZI may serve as an integrative node for global modulation of behaviors and physiological states. Zona incerta (ZI) is a largely inhibitory subthalamic region connecting with many brain areas. Early studies have suggested involvement of ZI in various functions such as visceral activities, arousal, attention, and locomotion, but the specific roles of different ZI subdomains or cell types have not been well examined. Recent studies combining optogenetics, behavioral assays, neural tracing, and neural activity-recording reveal novel functional roles of ZI depending on specific input–output connectivity patterns. Here, we review these studies and summarize functions of ZI into four categories: sensory integration, behavioral output control, motivational drive, and neural plasticity. In view of these new findings, we propose that ZI serves as an integrative node for global modulation of behaviors and physiological states. Zona incerta (ZI) is a largely inhibitory subthalamic region connecting with many brain areas. Early studies have suggested involvement of ZI in various functions such as visceral activities, arousal, attention, and locomotion, but the specific roles of different ZI subdomains or cell types have not been well examined. Recent studies combining optogenetics, behavioral assays, neural tracing, and neural activity-recording reveal novel functional roles of ZI depending on specific input–output connectivity patterns. Here, we review these studies and summarize functions of ZI into four categories: sensory integration, behavioral output control, motivational drive, and neural plasticity. In view of these new findings, we propose that ZI serves as an integrative node for global modulation of behaviors and physiological states.