receives synaptic input in region sends synaptic output to region GABA-Chol neuron medulla layer M3 medulla layer M4 medulla layer M8 transmedullary Y neuron transmedullary Y neuron TmY9 TmY9 FlyBrain_NDB:10177 fly_anatomy.ontology TmY9 FBbt:00003827 VFB:FBbt_00003827 The acetylcholine neurotransmitter was assessed by co-labelling cells with a Cha-GAL4.7.4 driver (FBtp0014830) and an anti-ChAT antibody (Varija Raghu et al., 2011). The GABA neurotransmitter was assessed by the intersection of the expression of the VGAT-GAL4 driver (FBtp0069181) and an antibody against GABA (Raghu et al., 2013). Pre- versus postsynaptic innervation judged by scoring of terminal morphology from figures in Fischbach and Dittrich (1989) as assessed by FlyBrain Neuron DB. Nern et al. (2025) - FBrf0262545 split this into TmY9a and TmY9b, but do not have distinct drivers for the subtypes. Transmedullary Y wide-field neuron that terminates with both fine and bleb-type arborizations in lobula layer 5, and in lobula plate layers 1 and 2. It displays both fine and bleb-type arborizations in medulla layers M3 and M8, but has only fine arborizations in medulla layer M4 (Morante and Desplan, 2008; Fischbach and Dittrich, 1989). It seems to be capable of both cholinergic and GABAergic neurotransmission (Varija Raghu et al., 2011; Raghu et al., 2013). lobula plate layer 1 lobula plate layer 2 lobula layer 5 adult cholinergic neuron adult GABAergic neuron optic lobe wide-field columnar neuron