Playing Stereoscopic Video Games Enhances the Precision But Not the Accuracy of Depth Perception

Playing Stereoscopic Video Games Enhances the Precision But Not the Accuracy of Depth Perception

Alvin Sherman Library

Purpose. We recently reported that playing immersive video games in a three-dimensions (3D) environment boosts stereo vision in young adults with normal vision. Here we asked whether the improvement in stereoscopic acuity (precision) was the result of a reduced disparity pedestal, as indicated by a decreased subjective depth bias (accuracy).

Methods. Twenty-one university students with normal visual acuity and stereoacuity were recruited. All of them had limited previous video game experience, and none had ever played 3D video games. Participants were required to play stereoscopic 3D video games for a total of 40 hours, 2 hours per session, over 4-5 weeks. Depth detection performance was measured using random dot stereograms before and after the video game intervention. Each random-dot stimulus consisted of a 1-degree central square of random dots embedded in a 3.3-degree square of random dots. A custom-built stereoscope was used to present a half monitor screen to each eye (i.e. the left square to the left eye and the right square to the right eye). A method of constant stimuli was used to measure stereo performance. The visual task was to determine the stereoscopic depth of the central square (in front or behind) relative to the outer reference square. No feedback to response was provided in each trial. Stereo acuity and bias (point of subjective equality) were defined as the disparity at the 84% (adjusted for zero bias, 1 standard deviation of response variability) and 50% correct response rates, respectively.

Results. In 81% of all observers, the point of subjective equality was behind the reference square (mean stereo bias: uncrossed disparities, 4.4 ± SE 2.0 arcsec; mean absolute, unsigned stereo bias: 7.8 ± SE 1.3 arcsec). After playing 3D video games, there was a statistically significant difference in stereoacuity (improvement in mean stereoacuity, 32.9%; mean difference=10.87 arcsec; paired t=2.941, p=0.005), but not in stereo bias (mean difference=0.25 arcsec; paired t=0.134, p=0.895).

Conclusions. Here we show that playing stereoscopic 3D video games modifies the precision, but not the accuracy of depth perception. These findings suggest that the enhanced stereoacuity did not result from reducing the effects of a disparity pedestal. These types of video games have potential therapeutic applications for improving stereo vision in patients with binocular vision anomalies.