Amplitude correlation envelope (AEC)

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1

Hi, would like to do Amplitude correlation envelope (AEC) computation, could not find that option in MNE-Connectivity.

Could anyone please guide of there is any method available in MNE for doing this, or how to compute AEC.

Help in this regard is much appreciated.
Thanks

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2

I think this is what you are looking for - Compute envelope correlations in source space — MNE-Connectivity 0.5.0 documentation

There is also a volume based measure (vs the surface based in the link)

–Jeff

3

Hi,

Could not find Amplitude correlation connectivity measure. Pls if anyone can help with how to compute amplitude correlation measure between set of electrodes, it would be really useful. Thanks

4

@jstout211

Could not find Amplitude correlation connectivity measure. I have to compute amplitude correlation measure between set of electrodes, it would be really useful if links to some resources can be shared. Thanks

5

Can you post a journal reference to the technique you are looking for? The hilbert envelope (referenced in the link) is the time resolved Amplitude of the band pass signal. Then you do correlation on the envelope amplitude to get your connectivity measure - hence Amplitude Envelope Correlation. I believe it is what you are looking for - but I could be wrong.

Regarding the connectivity between electrodes - I think you can do all of the steps except the things involved with the MRI (so ignore coreg/forward model and anything with stc and labels).

Just substitute epochs for stc/label_ts and it seems to run without error on a random dataset I tried it on.

corr_obj = envelope_correlation(
    >>epochs<<, orthogonalize='pairwise')
corr = corr_obj.combine()
corr = corr.get_data(output='dense')[:, :, 0]

I believe this will work - but I don’t routinely use this code - I just know that it is one of the example pages.

–Jeff

6

Thanks @jstout211, it was useful.