A neural Cartesian coordinate system for generating flexible internal goals

How do you navigate from your bedroom to your kitchen when it is out of sight? You must set a series of intermediate goals, 'waypoints', to steer relative to, and turn from. How do you set these intermediate goals? The answer to this is not yet well-understood. This is because neuroscientific investigation on navigation has typically been conducted on mammals, and the mammalian brain regions involved in navigation are confoundingly complex. However, the vinegar fly is also capable of navigating and remembering visual landmarks. Its brain contains a neural 'compass', and a single site of neural activity in that compass, i.e. a 'needle'. The position preferred by the needle helps the fly navigate towards its desired headings. I aim to understand how such headings are set relative to visual objects, moving us towards a general understanding of how animals set intermediate goals so that they can navigate smoothly.