EEG Data


#1

Hi all! I have some data from Muse monitor and am trying to understand my data, I have few questions:

  1. what is the sampling rate of Muse headband?
TimeStamp Delta_TP9 Delta_AF7 Delta_AF8 Delta_TP10 Theta_TP9 Theta_AF7 Theta_AF8 Theta_TP10 Alpha_TP9 Alpha_AF7 Alpha_AF8 Alpha_TP10 Beta_TP9 Beta_AF7 Beta_AF8 Beta_TP10 Gamma_TP9 Gamma_AF7 Gamma_AF8 Gamma_TP10
11:56:04 0.76663357 1.3523293 0.4053688 0.50788146 0.389212 0.67643434 0.009111157 0.1399862 0.81731164 0.89775306 0.19155622 0.78157306 0.94852656 0.44482195 0.75180274 0.76200294 0.6571261 0.22891413 0.47634113 0.5032194
11:56:05 0.76663357 1.3523293 0.4053688 0.50788146 0.389212 0.67643434 0.009111157 0.1399862 0.81731164 0.89775306 0.19155622 0.78157306 0.94852656 0.44482195 0.75180274 0.76200294 0.6571261 0.22891413 0.47634113 0.5032194
11:56:06 0.7482403 0.97426635 0.4053688 0.50788146 0.430507 -0.18799953 0.009111157 0.1399862 0.5859607 0.10314684 0.19155622 0.78157306 0.8281759 0.62776685 0.75180274 0.76200294 0.63212055 0.18084566 0.47634113 0.5032194
11:56:07 0.7482403 0.97426635 0.4053688 0.50788146 0.430507 -0.18799953 0.009111157 0.1399862 0.5859607 0.10314684 0.19155622 0.78157306 0.8281759 0.62776685 0.75180274 0.76200294 0.63212055 0.18084566 0.47634113 0.5032194
11:56:08 0.7482403 0.97426635 0.4053688 0.50788146 0.430507 -0.18799953 0.009111157 0.1399862 0.5859607 0.10314684 0.19155622 0.78157306 0.8281759 0.62776685 0.75180274 0.76200294 0.63212055 0.18084566 0.47634113 0.5032194
11:56:09 0.78170514 0.97426635 0.4053688 0.018751755 0.6831863 -0.18799953 0.009111157 -0.16026616 0.79398996 0.10314684 0.19155622 0.6952297 0.8123852 0.62776685 0.75180274 0.62214196 0.6386477 0.18084566 0.47634113 0.6546239
11:56:10 0.72341037 0.97426635 0.4053688 -0.11280259 0.5844922 -0.18799953 0.009111157 -0.115967795 0.7768295 0.10314684 0.19155622 0.6980085 0.7807979 0.62776685 0.75180274 0.53149545 0.6689447 0.18084566 0.47634113 0.6369871
11:56:11 0.33482632 0.97426635 0.77353436 0.3886727 0.05296254 -0.18799953 0.6223611 -0.103236906 0.16386895 0.10314684 0.62437135 0.61932355 0.7832462 0.62776685 1.0691215 0.62423754 0.617048 0.18084566 0.5051982 0.47552982
11:56:12 0.7944874 1.0155717 0.77353436 0.6216958 0.0809224 0.5283136 0.6223611 -0.051245224 0.40961167 0.50425786 0.62437135 0.62090427 0.7348861 0.6558609 1.0691215 0.6349203 0.55959535 0.067222275 0.5051982 0.43197036
  1. from the above dataset, what are the units of the data values for the brain waves - log of power or amplitude

#2
  1. Brainwaves are calculated at 10Hz, the raw EEG is 220Hz for the 2014 Muse and 256Hz for the 2016 and 2018 Muse’s.
    You can set the recording interval in Settings, but you only need the full rate if you want to calculate your own FFT’s on the raw EEG data.

  2. Log of Power Spectral Density.


#3

hello, I make several records, an in any of them the sampling rate is regular… why?


#4

I don’t understand your question, sorry. Please re-phrase.


#5

OK.

If calculate the sampling rate by every second separately, I got different values. Or if calculates the difference between one timestamp and the next, I also got different values (that should be all equal if there is a constant sampling rate).


#6

The timestamps are not consistent because of bluetooth buffering. If you search the forum you will find many posts on this. For FFT calcs you should assume a constant rate at source.


#7

I see. But in some records I have 2, 3, or only 10 timestamps per second. This is still because of Bluetooth buffering?


#8

Are you using Muse Monitor? If so, set the recording interval in settings to “Constant” and you will get 220hz or 256hz data depending on your Muse version. Bluteooth buffering will only alter the rate by a few hz.


#9

I already done that


#10

Email me a test recording and I’ll take a look: Support@MuseMonitor.com


#11

Hi,

a) I want to measure the ratios between the EEG waves.what do you recommend - 1)ratios between the log of power spectral density or 2. antilog the values and do ratios.
b) Why Muse is deleting missing data point.Is there is a setting i can change to monitor missing data points?


#12

#1 - I would just use the numbers as they are, you don’t need to do any logs.
#2 - Can you elaborate? I don’t understand your question.


#13
51:34.8 0.25917807 -0.005589217
51:35.8 0.48988882 0.16513857
51:36.8 0.13124159 -0.80538297
51:37.8 -0.30116874 -1.0120176
51:38.9 -0.07521598 -0.8901258
51:39.9 -0.067216836 -0.7150304
51:40.9 -0.31133035 -0.5905213
51:41.9 0.047955386 -0.43948606
51:43.0 0.13466813 -0.75240916

Observe the timestamp second from bottom, there is a missing data point - 51:42:…?


#14

Nothing missing there. Take note of the deltas.