I do not know. My not-being-an-anatomist strikes again. It is likely acrocerid vision has never been neurologically studied ever due to acrocerids being an obscure group. Your best bet is to research tabanids (the other family in which holoptic eyes that closely fused are common) instead. However:

at least some male tabanids have evolved a thing analogous to the four-eyedness of gyrinids and Anableps where the top half of both eyes is a different color and is specialized for scanning for mates. www.cell.com/current-biol...

thank you- and how interesting!