[FieldTrip] Problem with EEG channels in ft_neighborselection when running cluster statistics

[Stephen Politzer-Ahles]

When attempting to run cluster statistics on my EEG data (originally from
Neuroscan .CNT, then processed in EEGLAB and finally imported to fieldtrip)
using ft_timelockstatistics(), I receive the following error message:

??? Error using ==> ft_neighbourselection at 114
Did not find gradiometer or electrode information.

Error in ==> statistics_wrapper at 241
    cfg.neighbours = ft_neighbourselection(cfg,varargin{1});

Error in ==> ft_timelockstatistics at 123
[stat, cfg] = statistics_wrapper(cfg, varargin{:});

This seems to be because when I use cfg.channel = {'EEG'}; with my data, the
channel information (the variable "sens" used in ft_neighbourselection)
consists only of the list of channel labels:

sens =  {'FPZ'    'CPZ'    'FP2'    'F7' .........}

On the other hand, when I run timelockstatistics on the sample data from the
wiki, "sens" includes much more information:

sens =

      pnt: [151x3 double]
      ori: [356x3 double]
      tra: [184x356 double]
    label: {151x1 cell}
     unit: 'cm'

I think most of that extra information is planar gradient data (i.e., it
comes from GA_FIC.grad). Since my data are EEG data, I assume it wouldn't
make sense to use ft_megplanar on them. So, assuming that I need to get the
extra channel location information into my EEG data, does anyone have any
ideas on how to do that?

Best,
Steve Politzer-Ahles

-- 
Stephen Politzer-Ahles
University of Kansas
Linguistics Department
http://www.linguistics.ku.edu/
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