has soma location develops from receives synaptic input in region receives synaptic input from neuron lamina lamina monopolar neuron L2 columnar neuron T1 FlyBrain_NDB:10115 fly_anatomy.ontology An intrinsic columnar neuron whose cell body lies in the cortex of the medulla. The fiber of the T1 cell body branches at the medulla surface to form a T-shaped linking fiber between a bush-like arborization in the distal part of a medulla column (M1 and M2), and a bundle of climbing fibers in the equivalent column of the lamina (Fischbach and Dittrich, 1989). Synaptic connections in the lamina are exclusively postsynaptic and include a large number of connections from lamina intrinsic (amacrine) neurons (Meinertzhagen and O'Neil, 1991; Rivera-Alba et al., 2011). In the medulla, it is strongly synapsed by centrifugal neuron C3 in medulla layer M2 and lamina monopolar neuron L2 (Takemura et al., 2008; Takemura et al., 2013). There is usually one of these cells per optic column (Nern et al., 2025). T1 FBbt:00003727 Cell connectivity in the lamina was determined by analysis of semi-automated EM reconstruction of 749 serial sections of 21 complete lamina cartridges. The number of synaptic connections for T1 (presynaptic/postsynaptic) in a single lamina cartridge for each cell type was the following: R2 (-/2), R3 (-/2), R4 (-/2), Lai (-/54), C3 (-/1) and Lawf (-/1) (Rivera-Alba et al., 2011). Connectivity in the medulla was extrapolated from serial EM of 3 columns from a single sample (Takemura et al., 2008) or from 7 columns (Takemura et al., 2013). VFB:FBbt_00003727 T1 T neuron T1 centrifugal neuron C3 lamina intrinsic neuron Lai medulla layer M1 medulla layer M2 optic lobe intrinsic columnar neuron Notch OFF hemilineage secondary neuron immature columnar neuron T1 cell body rind of adult medulla