Visually Induced Motion Sickness During Smartphone Use in Moving Metro Carriages: Effects of Posture and Viewing...

Area of Science:

• Human-Computer Interaction
• Ophthalmology
• Ergonomics

Background:

• Smartphone use is prevalent during public transit.
• The combined impact of posture, viewing duration, and sex on visual fatigue and visually induced motion sickness (VIMS) during commuting is not well understood.

Purpose of the Study:

• To investigate the effects of posture (sitting vs. standing) and viewing duration (15 min vs. 30 min) on visual fatigue and VIMS during smartphone video consumption on public transit.
• To examine potential sex-based differences in these responses.

Main Methods:

• Forty healthy young adults (20 males, 20 females) participated in a randomized controlled study.
• Participants completed four conditions varying posture and viewing duration while watching videos on a smartphone aboard Taipei MRT carriages.
• Primary outcomes included critical flicker fusion frequency (CFF), visual fatigue scale (VFS) scores, viewing distance, and VIMS severity.

Main Results:

• Viewing duration had the most significant impact: 30 minutes of viewing increased visual fatigue and VIMS compared to 15 minutes.
• Standing posture exacerbated visual fatigue and VIMS, and shortened viewing distance compared to sitting.
• Females reported a steeper increase in visual fatigue over time, indicating a sex-by-duration interaction for VFS scores.

Conclusions:

• Extended smartphone viewing durations and standing postures are major contributors to visual and motion discomfort during metro commutes.
• Reducing continuous smartphone use time and adopting a seated posture can mitigate visual fatigue and VIMS.
• Further research is needed to confirm these findings in diverse commuter populations.