title: Alert response to motion onset in the retina.
abstract: Previous studies have shown that motion onset is very effective at capturing attention and is more salient than smooth motion. Here, we find that this salience ranking is present already in the firing rate of retinal ganglion cells. By stimulating the retina with a bar that appears, stays still, and then starts moving, we demonstrate that a subset of salamander retinal ganglion cells, fast OFF cells, responds significantly more strongly to motion onset than to smooth motion. We refer to this phenomenon as an alert response to motion onset. We develop a computational model that predicts the time-varying firing rate of ganglion cells responding to the appearance, onset, and smooth motion of a bar. This model, termed the adaptive cascade model, consists of a ganglion cell that receives input from a layer of bipolar cells, represented by individual rectified subunits. Additionally, both the bipolar and ganglion cells have separate contrast gain control mechanisms. This model captured the responses to our different motion stimuli over a wide range of contrasts, speeds, and locations. The alert response to motion onset, together with its computational model, introduces a new mechanism of sophisticated motion processing that occurs early in the visual system.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.
authors.forename: Eric Y
authors.initials: EY
authors.lastname: Chen
authors.forename: Olivier
authors.initials: O
authors.lastname: Marre
authors.forename: Clark
authors.initials: C
authors.lastname: Fisher
authors.forename: Greg
authors.initials: G
authors.lastname: Schwartz
authors.forename: Joshua
authors.initials: J
authors.lastname: Levy
authors.forename: Rava Azeredo
authors.initials: RA
authors.lastname: da Silveira
authors.forename: Rava Azeredo
authors.initials: RA
authors.lastname: da Silviera
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Berry
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000557:Ambystoma; D000818:Animals; D001288:Attention / Q000502:physiology; D009038:Motion; D009039:Motion Perception / Q000502:physiology*; D012160:Retina / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000502:physiology*