The electroretinogram (ERG) is a diagnostic test that measures the electrical activity of the retina in response to a light stimulus. The ERG arises from currents generated directly by retinal neurons in combination with contributions from retinal glia.

Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors (rods and cones), inner retinal cells (bipolar and amacrine cells), and the ganglion cells.

Aug 28, 2023 · The full-field electroretinogram (ffERG) is a specialized electrophysiologic test of retinal function in response to a full-field light stimulus. There are 6 standard protocols for isolating the electrical activity from the rods and cones. The ffERG is a valuable tool for objectively diagnosing and monitoring retinal disease.

May 1, 2001 · When a bright light stimulus is used to elicit the ERG in humans or in animals, low-amplitude oscillating waves can be identified on the rising phase of the b-wave. These wavelets are much faster than the complex of the a- and b-waves.

The ERG of the turtle eye (Fig. 1A) as elicited by a long (900ms) step of light, shows an a-wave and b-wave complex separated from the d-wave which is generated at stimulus offset. A bright light stimulus of 40sec duration is used to record the …

Read about electroretinography (ERG), an eye test where electrodes placed on the cornea measure electrical responses to light to try to detect abnormal retinal function.

Apr 20, 2020 · What is electroretinography? An electroretinography (ERG) test, also known as an electroretinogram, measures the electrical response of the light-sensitive cells in your eyes. These cells are...

The ERG has a specific abnormality showing a normal a-wave but no b-wave. It is a negative ERG (Fig. 24). The picture is similar to that recorded in central retinal artery occlusion and Congenital Stationary Night Blindness Type 2.

Jun 29, 2024 · The ERG is an extracellular potential that arises from currents that flow through the retina as a result of neuronal signaling and, for some slower ERG waves, potassium (K +) currents in glial cells. Local changes in the membrane conductance of activated cells give rise to inward or outward ion currents, and cause currents to flow in the ...

During the ERG test, the photoreceptors produce tiny amounts of electricity in response to brief flashes of light. A normal ERG contains an a-wave (initial negative deflection) followed by a b-wave (positive deflection).