Pattern Electroretinogram-based Contrast Gain of the Nondominant Eye Reflects Depressive States

Abstract

We often refer to negative mood states in daily life as “dark.” This is not merely a metaphor because psychological studies have reported that subjective brightness decreases with depression severity. Recent pattern electroretinogram (PERG) studies have reported lower retinal contrast gain in participants with higher depression scores. However, one study could not replicate this result, suggesting the need to improve the methodology. Past studies have averaged PERG values of both eyes when evaluating the relationship between the retinal contrast gain and depression scores. However, the PERG amplitudes differ between the dominant and nondominant eyes. Therefore, we separately assessed the relationship between depression scores and the average PERG of both eyes, the dominant eye and the nondominant eye. As a result, only the PERG-based contrast gain in the nondominant eye had a significant negative correlation with the Beck Depression Inventory score. This result suggests that measuring the PERG of the nondominant eye is more sensitive than the conventional method of using PERG to assess depression.