Looking for a complete hyperscanning solution for education? Find out how to run an auditory oddball experiment with multiple X.ons in a classroom
by Dr. Alex Kreilinger
Technical Product Manager (Brain Products)
With the release of the X.on in 2023, Brain Products broke new ground by making high-quality EEG equipment more affordable. Coupled with its easy-to-use design and unlimited and fast data access, this makes the new headset the ideal solution for educational and/or hyperscanning purposes.
Since the release, frequent and justified questions that reach us are: “Can we use multiple X.ons together in one room?” or “How many X.ons can we use simultaneously?”.
Typically—when dealing with wireless technology—the short answer to such questions is “it depends”, but we wanted to give you a more informed answer and decided to run some inhouse tests with multiple X.ons and perform a real EEG paradigm with actual participants.
How did our setup with multiple X.ons look like?
In order to test the hyperscanning capability of the X.on, we took 10 headsets, paired each of them with an Android™ phone, and set all of the parameters to maximum (sampling rate to 500 Hz, all possible channels activated, and reading LSL inlets on each phone).
Next, we constructed a classroom setting with benches and tables and set up a dedicated local wireless network. From the 10 X.on/phone pairs, 5 were sending noise and 5 were 5 were given to participants who were asked to wear the X.on on their head and hold the phone in their hands. All X.on/phone pairs were placed in close proximity, except for one “teacher” who was sitting a few meters aways and was also controlling the stimulus presentation software and taking care of the EEG recording.
When everything was properly set up, the participants were asked to listen to beeping sounds and perform a simple counting task. This auditory oddball paradigm was controlled by PsychoPy that played different auditory sounds (frequent, deviant, and target sounds). The participants were told to count only the target sounds (with the highest pitch) and to ignore the frequent and deviant sounds. Whenever a sound was played, it was accompanied by a corresponding LSL marker that was sent via the network. This LSL marker stream was picked up by all the phones and by LabRecorder. LabRecorder also recorded 10 LSL EEG streams and additionally 10 LSL marker streams that originated from each phone.
By adhering to a few important guidelines, it was possible to record from all 10 X.ons without any data loss. It was also possible to demonstrate clear and synchronized auditory ERPs for the 5 human participants. This could even be shown when people were allowed to move around the room freely.
Want to know more?
Please look up the comprehensive blog post on bci.plus for more information, especially to learn about important tips that make the recording of multiple streams a smooth experience and reduce the potential for data loss or other issues.
Do not hesitate to reach out to us if you have questions related to this topic or want to share your experience with us. We are always curious to learn great ideas our customers are working on.