The way in which the fly brain transforms visual information into motor actions is reported online this week in Nature Methods.
The fruit fly Drosophila melanogaster is an ideal organism to study how the brain processes visual cues and transforms them into locomotion. In most physiology experiments with living flies, the animals are held in positions that prevent natural movement of their legs. In a new technological feat, Jayaraman and colleagues devise a setup that presents flies with a visual stimulus and simultaneously records activity of some of their neurons using a genetically encoded calcium sensor. This was done while tracking the fly's movements as it walks on an air-supported ball.
The researchers saw that activity in the examined neurons was associated with specific walking behaviors in response to the visual cues. This technique will also allow studies related to learning and memory that are at present difficult to address mechanistically in other organisms.