XR and EEG
(Huseyin Beykoylu email 2025-03-07) VR-EEG setup has significant practical limitations
- challenging to fit the VR headset on the participant's heads without the over the head straps.
- the headset kept sliding downwards and very much disrupted the immersiveness of the experience as you can imagine.
(Huseyin Beykoylu email 2025-03-07) On using a Meta Quest 3 without the over-the-head strap.
This allowed us to retain more electrodes from the 32+2 biosemi layout. We ended up removing the Fp1, Fp2, O1, O2, and Oz electrodes as the top of the goggles and the (back of the) side straps were pushing hard on those electrodes.
(Huseyin Beykoylu email 2025-03-07)
Visual inspection of the data appeared relatively noise-free, but no analysys has been done so far.
Overall, if the immersiveness of the VR experience is central to your experimental manipulation, I'd advise against using the set-up we used (or something similar), as it was rather challenging to fit the VR headset on the participant's heads without the over the head straps. Plus, the headset kept sliding downwards and very much disrupted the immersiveness of the experience as you can imagine.
(Huseyin Beykoylu email 2025-03-07) Alternative
I'd invest in an integrated EEG-VR system.
Robert Oosterveld's Blog Interference and noise
The frequency of the electronics in the VR headset (and potentially the digital radio) is much higher than that of the EEG, and the EEG is low-pass filtered prior to digitization to avoid aliasing. That means that electronic noise of the headset, even though large in amplitude, might be sufficiently suppressed and not visible in the EEG. Furthermore, EEG in general is noisy anyway, also if you record it without a VR headset. So the artifacts you see might be more general in nature and relate to your task, your subjects behaviour, your EEG system, or the environment, rather than to the VR.
Robert Oosterveld's Blog Finding potential artifacts
I suggest that you do an EEG recording, alternating with the VR headset switched on and off (say for a minute each, and repeat that multiple times). That allows you to look for differences in the spectrum of the continuous EEG signal. In the same way you can experimentally evaluate other artifacts, for example movement artifacts (have the participant move with the VR headset on and without the headset and check for differences in the artifacts); it might well be that the artifacts are not related to the VR headset but merely to the movement.
Robert Oosterveld's Blog Artifacts and data analysis
Besides trying to avoid artifacts and cleaning the data, it is also important to consider the confounding effects on your analysis. Eventually you might want to do a statistical comparison; for that you should ideally design your experimental contrast such that there is no confounding effect (i.e., the artifacts – if present – are not different between conditions).
Weber et al., 2021 Note that interference below 50Hz is uncommon from HMDs
A main finding of the present study is that the signal quality of EEG measurements in combination with two contemporary HMDs remained _largely unaffected in frequencies below approx. 50 Hz_. The frequency range below 50 Hz includes the signal components that form the basis of the vast majority of contemporary, non-invasive EEG studies, which typically focus on signals such as in the alpha (8–13 Hz), beta (13–30 Hz), and theta (4–8 Hz) frequency range
Weber et al., 2021 Different HMDs present different interference
However, it has to be stated that these peaks occurred only during measures with the Oculus Rift and were not present for measures gained with the Vive Pro, which also has a refresh-rate of 90 Hz. Thus, differences in the electrical design of the two HMDs could possibly contribute to this effect.
[Ha et al., 2022 Controlled for eye-artifacts
Apparently an EOG is possible, even under the HMD.