[Mne_analysis] Temporal Resolution in Time-Frequency Analysis

[Maryam Zolfaghar]

        External Email - Use Caution        

Hi Phillip,

Thank you for the information.

1. During the band-pass filter before applying Hilbert, some level of
smoothing happens. That is why I want to know my exact temporal resolution
to report in the paper. In MNE examples, I saw the code " w_size = n_cycles
/ ((fmax + fmin) / 2.) # in seconds
<https://mne.tools/dev/auto_examples/decoding/plot_decoding_csp_timefreq.html#sphx-glr-auto-examples-decoding-plot-decoding-csp-timefreq-py>"
to calculate the infer window size but I am not sure whether this is the
way to calculate the temporal resolution according to the number of
cycles and the frequency of interests (fmin, fmax).

2. Thanks for the links. However, my question was more about the way they
implement the filter in eegfilt routine in MATLAB (a two-way least-square
FIR filter with maximally steep roll-offs and an extremely narrow
transition band).

I would be thankful if you could help me with the above questions.

Thanks,
-Mary



On Tue, Oct 1, 2019 at 3:26 PM Phillip Alday <phillip.alday at mpi.nl> wrote:

> The advantage to the Hilbert transform is that it more or less preserves
> the original temporal resolution but completely loses any frequency
> resolution (hence the need to filter beforehand, which does in a certain
> sense impact temporal resolution).
>
> Regarding your second question, a quick search yields a number of results:
>
>
> https://mne.tools/stable/search.html?q=filter&check_keywords=yes&area=default
>
> but especially
>
> https://mne.tools/stable/generated/mne.io.Raw.html#mne.io.Raw.filter
>
>
> https://mne.tools/stable/auto_tutorials/preprocessing/plot_30_filtering_resampling.html
>
> Phillip
>
>
> On 01/10/2019 23:07, Maryam Zolfaghar wrote:
>
>         External Email - Use Caution
> Hi all,
>
> I am analyzing my EEG signals through time-frequency methods and
> interested in the pre-stimulus alpha and theta band activity. The time
> resolution is important for my analysis. I have two very basic questions:
>             1.  I am wondering if there is any way to calculate the
> temporal precision/resolution after applying the Hilbert transform to get
> the power?
>             2. Also, is there any function similar to *eegfilt* in
> Matlab in MNE?
>
>
> Thank you,
> -Mary
>
> _______________________________________________
> Mne_analysis mailing listMne_analysis at nmr.mgh.harvard.eduhttps://mail.nmr.mgh.harvard.edu/mailman/listinfo/mne_analysis
>
>
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