Spatially displaced excitation contributes to the encoding of interrupted motion by the retinal direction-selective circuit

Abstract

Spatially distributed excitation and inhibition collectively shape a visual neurons receptive field (RF) properties. In the direction-selective circuit of the mammalian retina, the role of strong null-direction inhibition of On-Off direction-selective ganglion cells (ON-OFF DSGCs) on their direction selectivity is well-studied. However, how excitatory inputs influence the On-Off DSGCs visual response is underexplored. Here, we report that On-Off DSGCs have a spatially displaced glutamatergic receptive field along their preferred-null motion axis. This displaced receptive field contributes to DSGC null-direction spiking during interrupted motion trajectories. Theoretical analyses indicate that population responses during interrupted motion may help populations of On-Off DSGCs signal the spatial location of moving objects in complex, naturalistic visual environments. Our study highlights that the direction-selective circuit exploits separate sets of mechanisms under different stimulus conditions, and these mechanisms may help encode multiple visual features.