Dear Julia, If you want to parcellate the low-resolution (i.e. ~4k vertices per hemisphere) MEG source level time series, you first need to create the appropriate low-resolution dlabel file, sampled at 4k. The one you provided in your e-mail represents the parcellation at 32k vertices. This can be done using some clever combination of wb_commands, which involves splitting the dlabel.nii into two files (one for each cortical hemisphere), followed by a downsampling (using wb_command -label-resample). The appropriate low-level 4k spherical meshes are in the megconnectome software (in the template directory).
The MEG data does not have to be transformed in any way. Although the source time series have been computed in native space, due to the one-to-one vertex-wise correspondence across the different surface representations, individual vertices can be directly compared across subjects. Best wishes, Jan-Mathijs PS: alternatively, you can have a look here http://www.fieldtriptoolbox.org/tutorial/networkanalysis <http://www.fieldtriptoolbox.org/tutorial/networkanalysis>. This tutorial uses some data (available through FTP) which contains the parcellation you are looking for at the appropriate resolution (if memory serves me well). It is, however, represented as a matlab .mat file. > On 3 Nov 2017, at 18:58, Julia Hamilton <julia.hamil...@rutgers.edu> wrote: > > Hello, > > > We are working on parcellating HCP’s MEG data using the Glasser > 2016 parcels (inputFile and parcellationFile attached). The MEG data was > downloaded from > WU-Minn HCP Data-1200 Subjects Study, Source-Level Processed, Resting State > (dtseries) (ex. “100307_MEG_3-Restin_bfblpenv_betahigh.power.dtseries.nii”; > each file having ~8000 surface vertices). > > Although we had previously used the -cifti-parcellate function (below, via > Matlab) > to parcellate fMRI data, we are receiving errors when attempting to do so > with the MEG data. The following error occurred when using the > 100307_MEG_3-Restin_bfblpenv_betahigh.power.dtseries.nii as the inputFile. > > >> eval([‘!wb_command -cifti-parcellate ’ inputFile ‘ ’ parcellationFile ‘ > >> COLUMN > ’ outputFile]) > ERROR: no parcels found, output file would be empty, aborting > > We have access to the surface locations via the corresponding gifti files > (ex. “100307.L.midthickness.4k_fs_LR.surf.gii”, > attached), however, we are unsure how to incorporate this surface location > data into the dtseries file. > > We’re also unclear whether the MEG data needs to be transformed before > applying the > -cifti-parcellate function e.g. from native surface space (assumed to be the > original space of the MEG dtseries files) to MNI space. > > Any input or advice would be much appreciated! > > Thank you, > Julia Hamilton > 100307_MEG_3-Restin_bfblpenv_betahigh.power.dts... > <https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F1qXGWCsFXB11F3c6mEJ2eyQOYX-AR-WPj%2Fview%3Fusp%3Ddrive_web&data=02%7C01%7Cjulia.hamilton%40rutgers.edu%7C767af945945e4c2654ba08d522e42667%7Cb92d2b234d35447093ff69aca6632ffe%7C1%7C0%7C636453285659453379&sdata=DPoVj0G%2FzDRbMF9ST548wlpGM3vRKCB832II6TdKljU%3D&reserved=0> > _______________________________________________ > HCP-Users mailing list > HCP-Users@humanconnectome.org <mailto:HCP-Users@humanconnectome.org> > http://lists.humanconnectome.org/mailman/listinfo/hcp-users > <http://lists.humanconnectome.org/mailman/listinfo/hcp-users><100307.L.midthickness.4k_fs_LR.surf.gii><Q1-Q6_RelatedParcellation210.L.CorticalAreas_dil_Colors.32k_fs_LR.dlabel.nii> _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org http://lists.humanconnectome.org/mailman/listinfo/hcp-users
