and clusterrandomization

Eric Maris maris at NICI.RU.NL
Sat Jun 3 18:50:06 CEST 2006


Dear Olga,

> That was an inconsistency in the loci of EOG channels between subjects.
> Now I corrected it: HEOG and VEOG data are still presented in the data
> structure, but do not have the location (pnt 0 0 0). Is it OK? The results
> looks as what I excpected.

Because you never will include the EOG-channels in an analysis of the
EEG-channels, the location of the EOG is not required by
clusterrandanalysis.

greetings,

Eric Maris



> Best Regards,
> Olga.
>
> ----- Original Message -----
> From: "Eric Maris" <maris at NICI.RU.NL>
> To: <FIELDTRIP at NIC.SURFNET.NL>
> Sent: Friday, May 26, 2006 5:35 PM
> Subject: Re: [FIELDTRIP] and clusterrandomization
>
>
>> Dear Olga,
>>
>>
>> But the problems is still in my clusterrandomization.
>> Could the fact that the order of the channel in the file (C_vc11.label)
>> is not the same as in the C_vc11.elec.label influences the result of
>> clusterrandomization (I do not have my neigbouring channel file)?
>>
>>
>> That should not matter. However, the labels in your data structure
>> (.label in the output of timelockgrandaverage) should exactly match the
>> labels in the elec-structure. If that is OK, then something might have
>> gone wrong with the combination of the data of the different subjects. Do
>> they all have the same elec-structure? If the same physical channel has
>> different labels for different subjects, then this may create
>> inconsistencies between EEGlab and Fieldtrip. For Fieldtrip, channels
>> that have the same label are assumed to be physically identical, even if
>> they are in different positions in the data structure. This is only a
>> guess, of course.
>>
>>
>> kind regards,
>>
>> Eric Maris
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Best Regards,
>> Olga.
>>  ----- Original Message -----
>>  From: Ingrid Nieuwenhuis
>>  To: FIELDTRIP at NIC.SURFNET.NL
>>  Sent: Wednesday, May 24, 2006 8:45 PM
>>  Subject: Re: [FIELDTRIP] clusterrandomization on 3D-data within-subject
>>
>>
>>  Hi Olga,
>>
>>
>>
>>  About the z-param:
>>
>>  This is the field that contains the data to be plotted; for instance
>> 'avg', 'powspctrm' or 'cohspctrm'. Normally the function looks in your
>> data.dimord to find out which z-param to use. To make the function work
>> you could give cfg.zparam = 'avg' (for instance if you want to plot an
>> ERF/ERP). But if you could send me what the dimord field of the data that
>> you want to plot is, I could look why the plot functions don't extract
>> the correct zparam themselves.
>>
>>
>>
>>  About the timelockgranaveraging: I also think it should be the same. I
>> have no idea what it could be.
>>
>>
>>
>>  Good luck,
>>
>>  Ingrid Nieuwenhuis
>>
>>
>>
>>
>> ------------------------------------------------------------------------------
>>
>>  From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On
>> Behalf Of Olga Sysoeva
>>  Sent: Wednesday, May 24, 2006 5:44 PM
>>  To: FIELDTRIP at NIC.SURFNET.NL
>>  Subject: Re: [FIELDTRIP] clusterrandomization on 3D-data within-subject
>>
>>
>>
>>  Dear List member,
>>
>>
>>
>>  Sorry for such dull questions but,
>>
>>  I am again facing the new problems with Fieldtrip, although did not
>> solve some previous one (still can not singleplot and multiplot anything
>> 'cause of "unknown zparam field".
>>
>>
>>
>>  OK, about new one :-)
>>
>>
>>
>>  It seems that I did not use write the timelockgranaveraging.
>>
>>
>>
>>   The problem must be here, when I made grand averaging of all my 11
>> subject
>>   data
>>
>>                    cfg =[];
>>                     cfg.keepindividual = 'yes'
>>                     C_vc11  =
>>
>> timelockgrandaverage(cfg,vc_c_avg1,vc_c_avg2,vc_c_avg3,vc_c_avg4,vc_c_avg5,
>> vc_c_avg6,vc_c_avg7,vc_c_avg8,vc_c_avg9,vc_c_avg10,vc_c_avg11 );
>>
>>  As I understand the
>>
>>  vc_c_avg11.avg([9],[43]) should be similar with C_vc11.individual ([11],
>> [9], [43])
>>  But it is not.
>>  What can it be?
>>
>>  Best Regards,
>>
>>  Olga.
>>
>>
>>
>>
>>
>>    ----- Original Message -----
>>
>>    From: Olga Sysoeva
>>
>>    To: FIELDTRIP at NIC.SURFNET.NL
>>
>>    Sent: Saturday, May 13, 2006 4:34 PM
>>
>>    Subject: Re: [FIELDTRIP] clusterrandomization on 3D-data
>> within-subject
>>
>>
>>
>>    Thank you very much, Lilla!
>>
>>    Now I knwo what to do but faced the problem with " unknown zparam
>> field" when ploting the results. Unfortunatly cfg.zparam does not
>> discribed in help file...
>>
>>    Best Regards, Olga
>>
>>      ----- Original Message -----
>>
>>      From: Lilla Magyari
>>
>>      To: FIELDTRIP at NIC.SURFNET.NL
>>
>>      Sent: Saturday, May 13, 2006 3:11 PM
>>
>>      Subject: Re: [FIELDTRIP] clusterrandomization on 3D-data
>> within-subject
>>
>>
>>
>>      Dear Olga,
>>
>>
>>
>>      I am just studying time-frequency analysis but I have done already
>> on my data, so perhaps I can help you.
>>
>>      First, yes, you have to do freqanalysis on the preprocessed data of
>> the individual subjects for all conditions that you want to compare (i.e.
>> the input for this function contains all trials from one subject in one
>> condition.) And it is also important that the other input for this
>> function is the cfg where for example, in the cfg.method you have to
>> specify what kind of time-frequency analysis you want to use. (You have
>> to write 'wltconvol' for wavelet transformation and 'mltconvol' for
>> multitaper analysis.)
>>
>>      When you use freqanalysis as output you can get TFR for one subject
>> in one condition (but it is also possible to keep the information for the
>> individual trials of the condition by specifying cfg.keeptrials = 'yes').
>> When you have the TFRs for each subject you can grandaverage them with
>> freqgrandaverage where the input is the TFRs of all subjects (and before
>> averaging you can use also freqbaseline for giving a baseline for your
>> TFRs).
>>
>>
>>
>>      I hope it helps.
>>
>>
>>
>>      Best regards,
>>
>>      Lilla Magyari
>>
>>
>>
>>
>>
>>
>>
>>
>> --------------------------------------------------------------------------
>>
>>      From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On
>> Behalf Of Olga Sysoeva
>>      Sent: Saturday, May 13, 2006 9:28 AM
>>      To: FIELDTRIP at NIC.SURFNET.NL
>>      Subject: [FIELDTRIP] clusterrandomization on 3D-data within-subject
>>
>>
>>
>>      Dear list members,
>>
>>
>>
>>      Thank you everybody for your help! I've already got interesting
>> results using clusterrandomization on my data! Thanks a lot!
>>
>>
>>
>>      Now I have a question about using the clusterrandomization on 3-D
>> data (channel-time-frequency) in within-subject analysis.
>>
>>      As I understand it is possible with Fieldtrip, but I really newby in
>> time-frequency anlysis, therefore wanted your comments,
>>
>>      as far as I didn't find the example of the application of
>> clusteranalysis on this set of the data in tuturial.
>>
>>
>>
>>      I successfully conduct the within-subject clusterrandomization on my
>> grand-average data, which does not have the third, frequency demintion.
>>
>>      Now I want to add it. But I could not apply freqanalyisis on
>> grandavarage data, could I? Should I made the TFR of individual data and
>> than grand-avarage the result?
>>
>>      Which function should I use?
>>
>>
>>
>>      Best Regards,
>>
>>      Olga.



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