Direction Selective Neurons Responsive to Horizontal Motion in a Crab Reflect an Adaptation to Prevailing Movements in Flat Environments

FLORENCIA SCARANO; DANIEL TOMSIC; JULIETA SZTARKER

JOURNAL OF NEUROSCIENCE

SOC NEUROSCIENCE

Lugar: Washington, D.C.; Año: 2020 vol. 40 p. 5561 - 5571

0270-6474

All animals need information about the direction of motion to be able to track the trajectory of a target (prey, predator,cospecific) or to control the course of navigation. This information is provided by direction selective (DS) neurons,which respond to images moving in a unique direction. DS neurons have been described in numerous species includingmany arthropods. In these animals, the majority of the studies have focused on DS neurons dedicated to processing theoptic flow generated during navigation. In contrast, only a few studies were performed on DS neurons related to objectmotion processing. The crab Neohelice is an established experimental model for the study of neurons involved in visually-guided behaviors. Here, we describe in male crabs of this species a new group of DS neurons that are highly directionallyselective to moving objects. The neurons were physiologically and morphologically characterized by intracellularrecording and staining in the optic lobe of intact animals. Because of their arborization in the lobula complex, we calledthese cells lobula complex directional cells (LCDCs). LCDCs also arborize in a previously undescribed small neuropil ofthe lateral protocerebrum. LCDCs are responsive only to horizontal motion. This nicely fits in the behavioral adaptationsof a crab inhabiting a flat, densely crowded environment, where most object motions are generated by neighboringcrabs moving along the horizontal plane.