Preclinical Protocols

Functional Visual Biomarkers


Rod and Cone function can primarily be isolated in a-waves of photoptic and scotopic ERGs.

Diagnosys Protocols: Scotopic and Photopic ERG, Luminance Intensity Series, Flicker Frequency Series



Bipolar cell activity is primarily reflected in the B-wave of the ERG.

Diagnosys Protocols: Photopic and Scotopic ERG


Amacrine cell activity is primarily seen through oscillatory potentials (OPs) of an ERG and may also contribute to the PhNR response.

Diagnosys Protocols: Scotopic and Photopic ERG, PhNR

Retinal Ganglion Cells

Retinal Ganglion Cell activity is primarily measured by pattern ERG (PERG) and contributes to the PhNR response.

Diagnosys Protocols: PERG, PhNR


Retinal Pigmented Epithelium

RPE layer response is primarily identified by the C-wave curve.

Diagnosys Protocols: C-wave

Optic Nerve

The VEP response primarily measures optic nerve conduction to the visual cortex.

Diagnosys Protocols: pattern or flash VEP

Stimulate with flash and pattern


Choose any color, intensity, frequency, and duration of light for both photopic and scotopic ERG or VEP testing.


Select checkerboard, bar, grating, or multifocal stimulus patterns for both ERG and VEP tests.

Featured Protocols

Viz Path

Combines ERG, PhNR, C-wave, and VEP to assess the entire visual pathway.

viz path

Simultaneous Pattern ERG & VEP

Elicits a simultaneous response from the retina and visual cortex with pattern stimulation.

erg & vep

Scotopic Threshold Response (STR)

Detects light perception threshold with a dark-adapted flash intensity series.


Flicker Frequency Series

Tests cone responses to a progressively faster flicker stimulus.

flicker frequency

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