Related Experiment Video
Updated: Sep 13, 2025
Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
Luminance noise impacts putative luminance components of visual evoked potentials but not chromatic components
Bellany Barbosa Lopes1, Terezinha Medeiros Gonçalves Loureiro2, Felipe André da Costa Brito3
1Núcleo de Teoria e Pesquisa do Comportamento, Universidade Federal do Pará, Belém, Pará, Brazil.
Introduction:
Pseudoisochromatic stimuli are widely used in psychophysical color vision testing and the features of the luminance noise present on these stimuli have been reported modifying the psychophysical chromatic discrimination.
Objective:
The present study investigated how modifications in the luminance noise features (luminance contrast and number of luminance values) affect chromatic visual evoked cortical potentials (VECP) elicited by pseudoisochromatic gratings, aiming to evaluate the influence of luminance contrast and the number of luminance values in the pseudoisochromatic stimulus on the chromatic VECP.
Methods:
The sample consisted of seven young trichromatic participants. The waveforms of the visual evoked cortical potentials (VECP) were analyzed, focusing on the P1, N1, and P2 components across all stimulus conditions. The luminance noise contrast in the pseudoisochromatic stimulus had distinct effects on the amplitudes of the VECP components. Significant effects were observed for the amplitudes of the P1 (p = 0.01) and P2 (p = 0.04) components, while no significant effect was found on the amplitude of the N1 component (p = 0.3).
Results:
There was no significant effect of the luminance noise range on the latency of the VECP components (P1 VECP component, p = 0.54; N1 VECP component, p = 0.79; P2 VECP component, p = 0.49). The number of luminance values in the noise had no significant effect on VECP components amplitude and latency. Different manipulations of luminance noise influenced P1 and P2 VECP components and no modification of the luminance noise had influence on the main chromatic VECP component, N1 component.
Conclusion:
Manipulations in features of the luminance noise in pseudoisocrhomatic stimulus impacted in putative luminance components, but not chromatic components, of visual evoked potentials. The present findings may have potential applications in clinical neuro-ophthalmology, particularly for assessing congenital and acquired color blindness.
Related Concept Videos
01:22Photoreceptors and Visual Pathways
01:05Difference from Background: Limit of Detection
The LOD indicates the presence or absence...