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Retinal ganglion cells can rapidly change polarity from Off to On.

Geffen MN, de Vries SE, Meister M - PLoS Biol. (2007)

Bottom Line: The peripheral shift strongly modulates the strength of these two inputs in opposite directions, facilitating the On pathway and suppressing the Off pathway.Furthermore, we identify certain wide-field amacrine cells that contribute to this modulation.This study illustrates how inhibitory interneurons can rapidly gate the flow of information within a circuit, dramatically altering the behavior of the principal neurons in the course of a computation.

View Article: PubMed Central - PubMed

Affiliation: Program in Biophysics, Harvard University, Cambridge, Massachusetts, United States of America.

ABSTRACT
Retinal ganglion cells are commonly classified as On-center or Off-center depending on whether they are excited predominantly by brightening or dimming within the receptive field. Here we report that many ganglion cells in the salamander retina can switch from one response type to the other, depending on stimulus events far from the receptive field. Specifically, a shift of the peripheral image--as produced by a rapid eye movement--causes a brief transition in visual sensitivity from Off-type to On-type for approximately 100 ms. We show that these ganglion cells receive inputs from both On and Off bipolar cells, and the Off inputs are normally dominant. The peripheral shift strongly modulates the strength of these two inputs in opposite directions, facilitating the On pathway and suppressing the Off pathway. Furthermore, we identify certain wide-field amacrine cells that contribute to this modulation. Depolarizing such an amacrine cell affects nearby ganglion cells in the same way as the peripheral image shift, facilitating the On inputs and suppressing the Off inputs. This study illustrates how inhibitory interneurons can rapidly gate the flow of information within a circuit, dramatically altering the behavior of the principal neurons in the course of a computation.

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Dynamic Change of a Ganglion Cell's Visual MessageThe spike-triggered average stimulus of an On-Off cell, plotted for spikes (vertical tick marks) emitted in various 0.1-s intervals surrounding a peripheral shift. Each curve depicts the average intensity time course that caused a spike, and thus represents the average message such a spike sends to the brain. Dotted curve: the visual message that would have been conveyed by spikes in the interval 0.1–0.2 s, if the peripheral shift at 0 s had not occurred. Note that the dotted and solid curves for this interval differ significantly even at time points before the shift (arrows).
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pbio-0050065-g010: Dynamic Change of a Ganglion Cell's Visual MessageThe spike-triggered average stimulus of an On-Off cell, plotted for spikes (vertical tick marks) emitted in various 0.1-s intervals surrounding a peripheral shift. Each curve depicts the average intensity time course that caused a spike, and thus represents the average message such a spike sends to the brain. Dotted curve: the visual message that would have been conveyed by spikes in the interval 0.1–0.2 s, if the peripheral shift at 0 s had not occurred. Note that the dotted and solid curves for this interval differ significantly even at time points before the shift (arrows).

Mentions: Although all ganglion cell types experience a change in neural coding (Figure 2), the issue is most clearly illustrated by the On-Off cells. Figure 10 plots the visual message of such a neuron for spikes produced at different times before or after the image shift. When there is no motion in the periphery, a spike from this neuron reports a dimming within its receptive field. But shortly after a peripheral image shift, a spike stands for a brightening in the receptive field.


Retinal ganglion cells can rapidly change polarity from Off to On.

Geffen MN, de Vries SE, Meister M - PLoS Biol. (2007)

Dynamic Change of a Ganglion Cell's Visual MessageThe spike-triggered average stimulus of an On-Off cell, plotted for spikes (vertical tick marks) emitted in various 0.1-s intervals surrounding a peripheral shift. Each curve depicts the average intensity time course that caused a spike, and thus represents the average message such a spike sends to the brain. Dotted curve: the visual message that would have been conveyed by spikes in the interval 0.1–0.2 s, if the peripheral shift at 0 s had not occurred. Note that the dotted and solid curves for this interval differ significantly even at time points before the shift (arrows).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1808116&req=5

pbio-0050065-g010: Dynamic Change of a Ganglion Cell's Visual MessageThe spike-triggered average stimulus of an On-Off cell, plotted for spikes (vertical tick marks) emitted in various 0.1-s intervals surrounding a peripheral shift. Each curve depicts the average intensity time course that caused a spike, and thus represents the average message such a spike sends to the brain. Dotted curve: the visual message that would have been conveyed by spikes in the interval 0.1–0.2 s, if the peripheral shift at 0 s had not occurred. Note that the dotted and solid curves for this interval differ significantly even at time points before the shift (arrows).
Mentions: Although all ganglion cell types experience a change in neural coding (Figure 2), the issue is most clearly illustrated by the On-Off cells. Figure 10 plots the visual message of such a neuron for spikes produced at different times before or after the image shift. When there is no motion in the periphery, a spike from this neuron reports a dimming within its receptive field. But shortly after a peripheral image shift, a spike stands for a brightening in the receptive field.

Bottom Line: The peripheral shift strongly modulates the strength of these two inputs in opposite directions, facilitating the On pathway and suppressing the Off pathway.Furthermore, we identify certain wide-field amacrine cells that contribute to this modulation.This study illustrates how inhibitory interneurons can rapidly gate the flow of information within a circuit, dramatically altering the behavior of the principal neurons in the course of a computation.

View Article: PubMed Central - PubMed

Affiliation: Program in Biophysics, Harvard University, Cambridge, Massachusetts, United States of America.

ABSTRACT
Retinal ganglion cells are commonly classified as On-center or Off-center depending on whether they are excited predominantly by brightening or dimming within the receptive field. Here we report that many ganglion cells in the salamander retina can switch from one response type to the other, depending on stimulus events far from the receptive field. Specifically, a shift of the peripheral image--as produced by a rapid eye movement--causes a brief transition in visual sensitivity from Off-type to On-type for approximately 100 ms. We show that these ganglion cells receive inputs from both On and Off bipolar cells, and the Off inputs are normally dominant. The peripheral shift strongly modulates the strength of these two inputs in opposite directions, facilitating the On pathway and suppressing the Off pathway. Furthermore, we identify certain wide-field amacrine cells that contribute to this modulation. Depolarizing such an amacrine cell affects nearby ganglion cells in the same way as the peripheral image shift, facilitating the On inputs and suppressing the Off inputs. This study illustrates how inhibitory interneurons can rapidly gate the flow of information within a circuit, dramatically altering the behavior of the principal neurons in the course of a computation.

Show MeSH
Related in: MedlinePlus