A Neural Network for Wind-Guided Compass Navigation.

Spatial maps in the brain are most accurate when they are linked to external sensory cues. Here, we show that the compass in the Drosophila brain is linked to the direction of the wind. Shifting the wind rightward rotates the compass as if the fly were turning leftward, and vice versa. We describe the mechanisms of several computations that integrate wind information into the compass. First, an intensity-invariant representation of wind direction is computed by comparing left-right mechanosensory signals. Then, signals are reformatted to reduce the coding biases inherent in peripheral mechanics, and wind cues are brought into the same circular coordinate system that represents visual cues and self-motion signals. Because the compass incorporates both mechanosensory and visual cues, it should enable navigation under conditions where no single cue is consistently reliable. These results show how local sensory signals can be transformed into a global, multimodal, abstract representation of space. • The compass in the Drosophila brain is influenced by wind direction • Wind direction is conveyed to the compass via a specialized Ring neuron population • Ring neurons extract wind direction based on the displacements of both antennae • Compass neurons integrate wind and visual cues to produce a multimodal map of space Okubo et al. show that wind influences the compass in the Drosophila brain. They describe a pathway that connects mechanoreceptors to compass neurons, and they show how mechanosensory signals are transformed within this pathway. Their results demonstrate that the compass is a multimodal map, like the mammalian head direction map. [ABSTRACT FROM AUTHOR]