The Role of Striatal Neurovascular Coupling in Learning - Many sensory-guided behaviors are acquired through learning. Previous works indicated that the tail striatum, a caudal portion of the dorsal striatum, sits at the vital interface linking sensory inputs to motor outputs, and striatal plasticity plays an essential role in various types of reinforcement learning. Despite the accumulated understanding in neuronal activities, little is known how learning reshapes the striatal local network, including glial, lymphatic, and microvascular system, to support the establishment of associations between sensory inputs and motor outputs. Neurovascular coupling, the coupling of neuronal activity and microvascular dynamics, has been implicated in various physiological and pathological conditions. However, it remains largely unknown how behaviors such as a learning process, would modulate the dynamics of neurovascular coupling and in turn impact the learning process. Furthermore, due to limited methods, neurovascular coupling in subcortical regions (e.g., striatum) remains largely elusive. This study will use the newly established in vivo imaging methods, to explore the role of striatal neurovascular coupling in sensory perceptual learning. Aim 1 will determine the role of striatal functional neurovascular coupling in the perceptual learning. Neurovascular coupling will be temporally and reversibly blocked in the tail striatum during learning via manipulating nitric oxide, an essential vasoactive substance that mediates interactions between neurons and blood vessels. The dynamics of blood flow and neuronal activity will be monitored to validate the decoupling effects by nitric oxide manipulation, and assess its impact on task learning. Aim 2 will determine the dynamics of functional neurovascular coupling in the tail striatum during perceptual learning. First the dynamics of striatal neurovascular coupling during the learning process will be examined, and then the neuronal population(s) that mediates this change will be determined.
