A new paper was published today in Current Biology that features the first auditory connectome of any species and includes the discovery of 24 new types of neurons!
Male flies sing two types of “songs” in courtship: either a sine or pulse, and they switch between these modes in order to attract a female mate. The female moves closer to the male when she likes the tune, so the male adjusts what he sings accordingly. This is a pretty complicated behavior for such a small animal! The FlyWire FAFB dataset is a female (FAFB = full adult female fly brain), so researchers studied how she understands what she hears and interprets song into action (do I like this and move closer or nah, move back?). They found distinct groups of neurons that prefer either sine, pulse, or a combination of courtship songs. This is reminiscent of how retinal ganglion cells in Eyewire have a ‘preferred direction” of motion – these auditory neurons seem to have a preferred tune! By analyzing the network, Baker et al (Murthy and Seung Labs, Princeton) found that they could predict the response of neurons and that the organization of the network is nonhierarchical.
Lastly, here are a few cool images of drosophila auditory neurons: