Fig. 7.

BAmv1 builds the asymmetrical brain structure along the ventral surface of the fan-shaped body (FB). a Schematic frontal section of the brain at a central level, visualizing the FB and asymmetrical body (AB) with surrounding neuropil compartments. Input to the AB is exclusively provided by 16 pairs of BAmv1 neurons, forming the classes SA1, SA2, SA3 and SAF. Dendritic input of all of these neurons is derived bilaterally from the posterior part of the FB input domain; axonal output reaches preferentially the right AB, as visualized in the diagram. Note additional projection of neuron class SAF to layers 1 and 8 (highlighted in blue) of FB. A similar bifurcated projection is seen in atypical BAmv1 neurons FB1I and FB1J (schematized in grey). Excluded in this schematic is the sparse arborization of the DM4-FB1G neuron in the AB(Right). b Rendering of the hemibrain BAmv1 AB neurons, color coded as in schematic (a). Inset shows AB at higher magnification. c Heatmap depicting input neurons and their lineages of origin (vertical axis) on different classes of AB neurons (horizontal axis). Note that only a few lineages provide the large majority of input; each AB neuron group is targeted by a distinct combination of input lineages. For abbreviations see Table 1