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Everything that the brain sees must first be encoded by the retina, which maintains a reliable representation of the visual world in many different, complex natural scenes while also adapting to stimulus changes. This study quantifies whether and how the brain selectively encodes stimulus features about scene identity in complex naturalistic environments. While a wealth of previous work has dug into the static and dynamic features of the population code in retinal ganglion cells, less is known about how populations form both flexible and reliable encoding in natural moving scenes. We record from the larval salamander retina responding to five different natural movies, over many repeats, and use these data to characterize the population code in terms of single-cell fluctuations in rate and pairwise couplings between cells. Decomposing the population code into independent and cell-cell interactions reveals how broad scene structure is encoded in the retinal output. while the single-cell activity adapts to different stimuli, the population structure captured in the sparse, strong couplings is consistent across natural movies as well as synthetic stimuli. We show that these interactions contribute to encoding scene identity. We also demonstrate that this structure likely arises in part from shared bipolar cell input as well as from gap junctions between retinal ganglion cells and amacrine cells.
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This content will become publicly available on June 23, 2026
Contribution of Pannexin Channels to Afterimage Signals in the Amphibian Retina
Pannexin 1 (Panx1) forms large-pore, single-membrane channels that connect the intracellular and extracellular environments, permitting the passage of ions and small molecules such as ATP. Panx1 channels are involved in diverse signaling pathways that contribute to various physiological processes, including sensory processing, although their precise mechanisms of action remain incompletely understood. This study reveals a Panx1-mediated mechanism regulating visual signal processing in the amphibian retina. Using immunolabeling and confocal imaging, we localized Panx1 channels in the cone-dominated On-bipolar cells, specifically at both somas and axon terminals. Whole-cell patch-clamp recordings showed that these channels have high permeability to Cl⁻ ions, which can be blocked by10Panx1 peptide, carbenoxolone, and mefloquine, all recognized as Panx1 inhibitors. Blocking Panx1 channels or reducing external Cl⁻ concentrations significantly increased bright light-induced delayed spontaneous excitatory responses in ganglion cells, indicating an inhibitory role of Panx1 channels at the bipolar cell synaptic release. These delayed spontaneous responses in ganglion cells, known as rebound currents, are associated with afterimage signals in the retina. Our findings suggest that Panx1 channels help prevent over-excitation associated with bright light-induced afterimage phenomena.
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- Award ID(s):
- 2126141
- PAR ID:
- 10612839
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- American Journal of Physiology-Cell Physiology
- ISSN:
- 0363-6143
- Subject(s) / Keyword(s):
- Pannexin retina bipolar cells ganglion cells afterimages
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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