I found some noises appearing in my EEG recordings. As shown in the attached screenshot, at channels 11 and 13, there are some high-frequency oscillations going on.
I’m using the EGI system. The data is 0.1 Hz high-pass filtered and 60 Hz notch filtered, then segmented. Although I’m only showing one trial, the noise is throughout the whole recording. I’m wondering if there is something wrong or it’s just some “regular” noises.
I also attached the data file here in case you want to take a look.
Any input is appreciated. Thank you.
That looks like EMG noise to me. I guess those electrodes are near the face or neck. Hopefully an ICA will be able to isolate the noise so you can project it out.
Some people just have tonic EMG noise like this. I think some people just have a lot of muscle tension continuously – and probably unconsciously. It could be due to bad posture, sitting in an uncomfortable position, or perhaps anxiety.
In my experience, this kind of noise tends to be continuous over time and unrelated to the tasks, so if ICA doesn’t remove it, then hopefully the baseline normalization and/or condition comparisons will normalize it out.
Thank you, Mike.
Yes, these are frontal electrodes near the face.