Most animals take advantage of multiple information sources to form a coherent percept of the world for adaptive behavioral decisions. These processes occur in complex neural networks embedded in the central nervous system that are typically difficult to identify and to study at the cellular level. Accordingly, a full understanding of the principles underlying multimodal information processing and decision-making has lagged behind. This project aims to significantly extend our understanding of single neurons and their roles in central computation. Specifically, it will address a common yet little understood sensorimotor integration phenomenon: how neurons process multimodal sensory inputs with different temporal characteristics, for example, gradual visual motion stimuli and abrupt sounds. For this purpose, the networks that mediate the fish startle-escape behavior will be used. These networks are unique, because they involve definable decision-making neurons, the Mauthner cells, which receive multimodal inputs and can be studied with electrophysiological and behavioral techniques. A guiding idea for the proposal is that the timing and balance of neural excitation and inhibition play a significant role in information processing and the expression of behavior. These characteristics are directly relevant to nervous system disorders in which this balance is impaired. The multidisciplinary components of this project allow the involvement of students at different levels of training and experience and thus will provide outstanding educational and outreach opportunities. The generation of preliminary results already has involved high school, undergraduate, graduate, and postdoctoral students.
Multimodal integration enhances our perception when the signal from a single sense organ is weak or deprived. Elucidating the principles and mechanisms by which different senses interact will be very useful in designing/optimizing the sensory environment of people or machines performing perceptually demanding tasks.