Abstract
Here, we describe a technique for charting the inputs of individual Kenyon cells in the Drosophila brain. In this technique, a single Kenyon cell per brain hemisphere is photo-labeled to visualize its claw-like dendritic terminals; a dye-filled electrode is used to backfill the projection neuron connected to each claw. This process can be repeated in hundreds of brains to build a connectivity matrix. Statistical analyses of such a matrix can reveal connectivity patterns such as random input and biased connectivity. For complete details on the use and execution of this protocol, please refer to Hayashi et al. (2022).1.