We are interested in understanding the neural and circuit basis of visually guided choice behavior, decision-making, associative learning, and behavioral flexibility. For example, how is visual information processed by specific components in the neural circuit to generate specific visual perception and motor behavior? How do sensory experience, trial history, and behavioral context influence neural computation to guide behavior? Using the mouse model, we address these questions by studying several brain regions important for perceptual decision making: visual cortex, posterior parietal cortex, orbitofrontal cortex, secondary motor cortex, and striatum. Our techniques include multi-electrode recordings, in vivo and in vitro whole-cell patch recordings, fiber photometry, optogenetic/pharmacogenetic manipulation, immunohistochemistry, and mouse behavior.
Neural mechanism of sensory-guided choice behavior
Studies in primates point out that sensory-guided choice behavior involves neural computations in several interconnected brain regions, including prefrontal cortex, parietal cortex, sensory cortex, basal ganglia, and superior colliculus. However, the contribution of specific cell types in each region to specific behavioral process, and the functional connectivity among these brain regions, remain unclear. We have established visual- or olfactory-guided choice behavior in freely-moving or head-fixed mice. To understand the neural mechanism of sensory-guided choice behavior, we are now performing chronic recordings, pharmacogenetic/optogenetic manipulations, or optogenetic tagging of specific cell type in brain regions including the secondary motor cortex, orbitofrontal cortex, and dorsal striatum.
Neural circuit mechanism contributing to visual associative learning
During associative learning, humans and animals need to update the representation of environmental cues associated with desired outcomes. As part of the prefrontal cortex, the orbitofrontal cortex (OFC) plays an important role in a variety of complex functions, such as reward coding, decision making, and flexible behavior. OFC lesions impair prediction error signals in the midbrain dopaminergic neurons. The OFC also connects with the sensory cortices, including the primary visual cortex (V1). We are now studying (1) How does the OFC projection to V1 influence V1 responses in behaving mice? (2) How do V1-projecting OFC neurons respond during visual behavior? (3) How does the OFC projection to V1 influence visual associative learning?