Special Biology Seminar

Abstract:

To survive in dynamic environments, animals shift between behavioral states based on their recent experience. Because these shifts are supported by neuronal networks that can be distributed throughout the brain, we have developed whole-brain cell-resolution light-sheet calcium imaging techniques to image activity in almost all neurons in larval zebrafish swimming in virtual environments. Since glial cells exhibit dynamic responses and intimately associate with neurons throughout the entire brain, we also developed tools for imaging and manipulating astrocytes. We discovered that astrocytes, driven by noradrenergic neuromodulatory neurons, accumulate evidence that current actions are ineffective and consequently drive sudden changes in behavioral states. In this talk I will report on these findings and also on a surprising set of results implying that the serotonergic system stores the memory of the effectiveness of recent motor commands in order to adjust the graded vigor of ongoing motor outflow.