Purchase this article with an account.
A.J. Zhang, J. Zhang, Z. Yang, S.M. Wu; Receptive Field Organization, Morphology and Patterns of Dye Coupling of Amacrine Cells and Ganglion Cells in the Tiger Salamander Retina . Invest. Ophthalmol. Vis. Sci. 2006;47(13):3104.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
The objective is to understand bipolar cell synaptic inputs and the center–surround antagonistic receptive field (CSARF) organizations of various types of third–order neurons in the vertebrate retina.
Retinal neurons were impaled with microelectrodes filled with Neurobiotin and Lucifer yellow in superfused flatmount retinas of the tiger salamander, and voltage responses to light spots or annuli of various diameters were recorded. Cell morphology and patterns of dye coupling were examined with a confocal microscope, and the cells’ relative rod/cone inputs were analyzed by the spectral difference method.
Receptive field center diameters of sustained amacrine cells and ganglion cells varied from 400 to 800µm, and they displayed antagonistic surround responses. Most sustained ganglion cells exhibit cone dominated responses, and the voltage gain of the bipolar–ganglion cell synapses varied from 5 to 10. ON–OFF amacrine cells and ON–OFF ganglion cells have larger receptive fields, and they did not exhibit CSARF. These cells showed mixed rod/cone inputs with a bipolar–ganglion cell voltage gain of about 20–40. Amacrine cells and ganglion cells were dye coupled with cells of the same subtypes, but some ganglion cells were dye coupled with amacrine cells.
The receptive field size of retinal neurons is positively correlated with their dendritic field diameter and degree of dye coupling. Cells with smaller receptive field centers and/or with stronger cone inputs exhibit more robust antagonistic surround responses. Third–order retinal neurons with transient ON–OFF responses have large receptive fields but poor CSARF, and they are therefore more likely to encode motion rather than contrast.
This PDF is available to Subscribers Only