UMD Researchers Identify Brain Signals Linked to ‘Cybersickness’

You slip on a virtual reality (VR) headset for a required safety training course on how to shut down a malfunctioning machine, and soon you’re nauseous enough to worry about having an accident of your own. Or, during a long-anticipated museum tour, the augmented reality (AR) information display from the smart glasses you’re borrowing makes you dizzy instead of delighted.

For years, developers of AR and VR technologies have worked to address this “cybersickness,” a type of motion sickness triggered in a majority of users by the movement of digital content.

In a new study published last month in the journal Virtual Reality, University of Maryland scientists used electroencephalography (EEG) to identify changes in brain wave activity while participants viewed virtual content designed to induce cybersickness. The findings offer real-time signals that could help designers detect and reduce cybersickness symptoms as they occur.

“VR and AR technologies aren’t just for gaming anymore. They’re used in healthcare, teaching, job training, building design and even to plan surgeries, but their effectiveness is compromised by cybersickness,” said Mattie Johnson, a UMD computer science doctoral student and the study’s first author. “

The new study, led by computer science Professor Amitabh Varshney and supported by a National Science Foundation award, was conducted in collaboration with the Food and Drug Administration and Sony Group Corp. The researchers focused on cybersickness associated with the vergence-accommodation conflict (VAC): a mismatch between where the eyes converge to view an object and the distance at which they focus.

In the real world, these two distances generally correspond. In many VR and AR displays, however, the eyes may converge on a virtual object that appears near or far while focusing on a display set at a fixed focal plane. This mismatch is an inherent challenge for many immersive displays and is believed to contribute to visual discomfort and cybersickness.

“We showed in an earlier study that EEG can be a reliable indicator of vection-induced cybersickness, which occurs when a virtual environment creates an illusion of self-motion while the user’s physical body remains completely still,” said Varshney, who has a joint appointment in the University of Maryland Institute for Advanced Computer Studies and serves as dean of the College of Computer, Mathematical, and Natural Sciences. “This new study expands those findings to a second type of cybersickness and provides an important foundation for making immersive technologies more comfortable and accessible.”

Cybersickness can cause nausea, dizziness, sweating, blurred vision, disorientation and more. In previous studies, 65.2% of VR users reported experiencing cybersickness, including 23.9% who reported severe symptoms. Researchers traditionally assess cybersickness with the Simulator Sickness Questionnaire (SSQ), a 16-question survey developed in 1993 to evaluate U.S. military fighter pilots’ experiences while using flight simulators. While the questionnaire remains useful, it relies on participants’ reports after an immersive experience and does not provide continuous measurements during exposure.

“A lot of people use the questionnaire in VR studies, but it’s a subjective way to measure,” said paper co-author Sujal Bista, director of the Immersive Visualization Center at the University of Maryland Institute for Health Computing (UM-IHC). “It also doesn’t allow for continuous data collection from the user. We needed a better way to measure in real time.” 

The researchers recruited 40 participants and recorded their brain activity using a 64-electrode EEG system while they wore a Meta Quest 2 headset and experienced an immersive environment that induced VAC. Participants completed the SSQ after exposure so the researchers could compare self-reported symptoms with the EEG data.

The EEG recordings showed changes in activity across several brain wave frequency bands during cybersickness.

“In the frontal lobe, we found a statistically significant decrease in high brain wave frequencies during cybersickness, and in the occipital lobe we saw a statistically significant decrease in low brain wave frequencies,” Johnson explained. “These changes in what we call EEG clusters could be useful predictors of a cybersickness experience.” 

For scientists, predicting cybersickness is just the first step. Ultimately, the team aims to help inform the development of technology to mitigate symptoms in real time, improving user comfort and productivity over extended periods of immersion, Johnson said. 

One possible approach would involve communication between an EEG-monitoring device and a VR headset. If the EEG system detected a pattern associated with emerging cybersickness, the headset could adjust the virtual scene — for example, by bringing the displayed content closer to the headset’s focal plane and reducing the vergence-accommodation conflict.

UM-IHC researchers Barbara Brawn, Jonathan Heagerty and Sida Li also co-authored the paper.