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  • Spatially displaced excitation contributes to the encoding of interrupted motion by a retinal direction-selective circuit
Title: Spatially displaced excitation contributes to the encoding of interrupted motion by a retinal direction-selective circuit
Spatially distributed excitation and inhibition collectively shape a visual neuron’s 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 DSGC’s visual response is underexplored. Here, we report that On-Off DSGCs have a spatially displaced glutamatergic receptive field along their horizontal preferred-null motion axes. 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.  more » « less
Award ID(s):
1652617
PAR ID:
10336101
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
eLife
Volume:
10
ISSN:
2050-084X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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