EEGLAB time frequency analysis question

The figure above is the EEGLAB sample data and the figure below is the time frequency analysis result for the EEG data I measured. The difference between the two figures is clear, and I don't know why my data shows that shape. I don't know how to get the data in a clear and tidy form like the sample data. Is my measurement method wrong?

Answer 1

[Angelo Yeo]

No one can answer whether your measurement method is wrong or not only with the figure you provided.

However there are a few things I can find:

1) The second figure does not show you a signal from a channel but an independent component. This does not show you the channel activity but a linear combination of all the signals.

2) The first IC components shows the biggest signal component. Most of the time, this includes eye movement but I do not see any eye movement-related signals but a very big activity on the left parieto-occipital region.

3) It seems like you are performing an event-related experiment. However, the ERP signal does not show you any ensembled activity locked at 0 sec. Did you epoch correctly? And why aren't there any baseline time period?

I don't think this is from brain activity. It might be a noise component from outside.

[sam]

Thank you for answer I think my problem stemmed from my lack of foundation in EEG analysis methods. We fixed this problem by entering the epoch according to the markers. thank you

[Angelo Yeo]

It's good to know that the issue is resolved! Thank you for leaving the comment.