lobula plate layer 1 FBbt:00040018 lobula plate layer A Layer of the lobula plate that abuts the second optic chiasm (Fischbach and Dittrich, 1989). The dendritic arbors of the horizontal system neurons are found exclusively in this layer, alongside terminals of the T4a and T5a neurons (Fischbach and Dittrich, 1989). Neurons in this layer are sensitive to diagonal front-to-back motion, i.e. front top to back bottom or front bottom to back top (Henning et al., 2022). front-to-back layer layer Lop1 HS layer VFB:FBbt_00003886 fly_anatomy.ontology FBbt:00003886 lobula plate layer