Walking strides direct rapid and flexible recruitment of visual circuits for course control inDrosophila

Flexible mapping between activity in sensory systems and movement parameters is a hallmark of successful motor control. This flexibility depends on continuous comparison of short-term postural dynamics and the longer-term goals of an animal, thereby necessitating neural mechanisms that can operate across multiple timescales. To understand how such body-brain interactions emerge to control movement across timescales, we performed whole-cell patch recordings from visual neurons involved in course control in Drosophila . We demonstrate that the activity of leg mechanosensory cells, propagating via specific ascending neurons, is critical to provide a clock signal to the visual circuit for stride-by-stride steering adjustments and, at longer timescales, information on speed-associated motor context to flexibly recruit visual circuits for course control. Thus, our data reveal a stride-based mechanism for the control of high-performance walking operating at multiple timescales. We propose that this mechanism functions as a general basis for adaptive control of locomotion.