[FieldTrip] extracting individual trial phase connectivity

Hwee Ling Lee hweeling.lee at gmail.com
Thu Sep 18 14:30:16 CEST 2014


Dear all,

I've got a question regarding extracting pairwise phase consistency of
individual trials for each subject.

Using the connectivity analyses tutorial as a reference, I extracted the
PPC using the fourier information from the mtmfft (dpss taper).

Here's an example of my code:

    cfg                 = [];
    cfg.output          = 'fourier';
    cfg.channel         = {'all'};
    cfg.method          = 'mtmfft';
    cfg.keeptrials      = 'yes';
    cfg.tapsmofrq       = 5;

    % find the index for the c200 condition
    pre_c200_idx = find(data8.trialinfo == 200);

    cfg.trials          = pre_c200_idx;
    cfg.foilim          = [0 100]; % either the full range of frequencies
(data2.hdr.Fs/2) or up to 100 Hz
    cfg.taper           = 'dpss';
    HLF_pre_c200        = ft_freqanalysis(cfg, data8);

The PPC is extracted using this code:

    cfg                 = [];
    cfg.trials          = 'all';
    cfg.keeptrials      = 'yes';
    cfg.channel         = {'all'};
    cfg.removemean      = 'yes';

    cfg.method           = 'wppc';
    cfg.channelcmb       = {cfg.channel, cfg.channel};

    HLF_pre_c200wppc      = ft_connectivityanalysis(cfg, HLF_pre_c200);

Although I've specified to keep individual trials, my output is still a
'chan_freq' dimord variable. It does not contain any individual trial PPC
information. Is there a way to extract the connectivity for individual
trials?

Thanks.

Cheers,
Hweeling
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20140918/293d85c9/attachment-0001.html>


More information about the fieldtrip mailing list