adult medial antennal lobe tract [FBbt_00003985]

adult medial antennal lobe tract

ID: FBbt_00003985

A tract of about 200 axons that emerges from the posterior dorsomedial area of the antennal lobe (dorsomedial root), the same root as the mediolateral antennal lobe tract (mlALT) and transverse antennal lobe tract (tALT). It runs dorsoposteriorly along the posterior surface of the fan-shaped body, turns laterally in front of the protocerebral bridge, passes in front of the mushroom body calyx and terminates in the lateral horn. It contains axons of antennal lobe projection neurons, some of which terminate in the main calyx and dorsal accessory calyx (Yagi et al., 2016). It demarcates the boundaries of the lateral accessory lobe (medial region), vest (superior region), epaulette (medial region), fan-shaped body (lateral region), gorget (superior region), inferior clamp (lateral and superior-lateral regions), inferior bridge (superior-lateral region), antler (lateral region), superior clamp (posterior-superior region), mushroom body calyx (anterior region) and superior lateral protocerebrum (inferior region). It contains fibers from the BAlc (ALl1), BAlp4 (ALlv1), BAmv3 (ALad1) and DPMpm1 (DM2) lineages (Lovick et al., 2013).

Two smaller tracts branch from the main mALT. One contains several branches and begins near the medial surface of the mushroom body calyx, projects anteriorly and terminates in the ring neuropil. The second tract begins in front of the mushroom body calyx and projects into it. Some of the projection neurons that fasciculate with the mALT send collateral branches to the posterior lateral protocerebrum (PLP) via the lateral section of the posterior lateral fascicle (PLF) and to the ring neuropil via the superior section of the PLF (Tanaka et al., 2012).