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Characterization of multi-input electroretinogram using normal control subjects.

H Ohguro·M Saito·K Ogawa·T Nakagawa
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Abstract

BACKGROUND: The multi-input electroretinogram (ERG) has recently been developed to analyze focal retinal responses in the central region and is expected to become a powerful tool for management of retinal diseases. The relationship between the obtained ERG response and retinal neuronal functions is not yet fully understood. METHOD: In the present study, in order to study the spatial retinal functions; multi-input ERGs were recorded from 14 healthy subjects under several illumination conditions modulating photoreceptor functions. RESULTS: The first-order kernel amplitudes were changed in correspondence to the cone photoreceptor adaptation states under different background illuminations. A strong flash exposure significantly lowered the amplitude (approximately 70%) within the central 15 deg but lowered it only slightly (10-20%) in the peripheral areas outside the central 15 deg. Similar effects were observed when the stimulus luminance was lowered by neutral density filters. CONCLUSION: Our data suggest that a newly developed multi-input measurement of ERGs represents signals within the firing of postreceptor neurons from cone photoreceptors at specific areas. Thus, this analysis is a useful tool for mapping the spatial network of neurons in the central region.

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AdultDark AdaptationElectroretinographyHumansNeuronsPhotic StimulationPhotoreceptor Cells, VertebrateVision, OcularJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

H Ohguro, M Saito, K Ogawa, T Nakagawa. 1998. Characterization of multi-input electroretinogram using normal control subjects.. https://doi.org/10.1007/s004170050167

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