  When using Head-Mounted Displays (HMDs), users may not always notice or
report visual discomfort by blurred vision through unadjusted lenses, motion
sickness, and increased eye strain. Current measures for visual discomfort rely
on users' self-reports those susceptible to subjective differences and lack of
real-time insights. In this work, we investigate if Electroencephalography
(EEG) can objectively measure visual discomfort by sensing Event-Related
Potentials (ERPs). In a user study (N=20), we compare four different levels of
Gaussian blur in a user study while measuring ERPs at occipito-parietal EEG
electrodes. The findings reveal that specific ERP components (i.e., P1, N2, and
P3) discriminated discomfort-related visual stimuli and indexed increased load
on visual processing and fatigue. We conclude that time-locked brain activity
can be used to evaluate visual discomfort and propose EEG-based automatic
discomfort detection and prevention tools.
