# Effects of Acute Mental Stress on Choroidal Thickness

## TL;DR

This study found that acute mental stress causes temporary thickening of the choroid, which may relate to eye health and myopia progression.

## Contribution

The novel contribution is demonstrating a direct link between acute mental stress and choroidal thickness changes using SS-OCT and deep learning segmentation.

## Key findings

- Mental arithmetic caused significant thickening in choroidal thickness at 1 mm and 3 mm foveal regions.
- The CT3mm showed a larger and more statistically significant increase compared to CT1mm during mental stress.
- The results suggest acute mental stress may influence choroidal dynamics, potentially impacting myopia progression.

## Abstract

Purpose: Previous studies have indicated an association between education and myopia, suggesting that numerous stress events during the educational process may influence eye health. This study aimed to investigate the impact of mental stress induced by mental arithmetic (MA) on choroidal thickness (CT). Methods: This study included 33 participants aged between 19 and 29 years. Swept-source optical coherence tomography (SS-OCT) was used to capture images of the posterior segment of the left eye during baseline and MA to assess changes in the CT. After denoising and compensation, the baseline images and MA images that had been rigidly registered and resampled to the baseline images were segmented using a deep learning-based method. Based on the segmentation results, the CT within the regions of 1 mm and 3 mm diameter centered at the lowest point of the fovea was calculated. Results: Significant increases were observed in both CT1mm and CT3mm during MA, with mean changes of 2.742 ± 7.098 μm (p = 0.034) and 3.326 ± 6.143 μm (p < 0.001), respectively. Conclusions: Thickening of the choroid has been observed during acute mental stress. We speculate that long-term or chronic mental stress could have a potential adverse impact on myopia progression.