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reference:ft_electrodeplacement [2018/08/23 14:43]
reference:ft_electrodeplacement [2018/08/23 14:43] (current)
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 +Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_electrodeplacement"​.
 +  <a href=/​reference/​ft_electrodeplacement><​font color=green>​FT_ELECTRODEPLACEMENT</​font></​a>​ allows manual placement of electrodes on a MRI scan, CT scan
 +  or on a triangulated surface of the head. This function supports different methods.
 +  VOLUME - Navigate an orthographic display of a volume (e.g. CT or MRI scan), and
 +  assign an electrode label to the current crosshair location by clicking on a label
 +  in the eletrode list. You can undo the selection by clicking on the same label
 +  again. The electrode labels shown in the list can be prespecified using cfg.channel
 +  when calling ft_electrodeplacement. The zoom slider allows zooming in at the
 +  location of the crosshair. The intensity sliders allow thresholding the image'​s low
 +  and high values. The magnet feature transports the crosshair to the nearest peak
 +  intensity voxel, within a certain voxel radius of the selected location. The labels
 +  feature displays the labels of the selected electrodes within the orthoplot. The
 +  global feature allows toggling the view between all and near-crosshair
 +  markers. The scan feature allows toggling between scans when another scan
 +  is given as input.
 +  HEADSHAPE - Navigate a triangulated scalp (for EEG) or brain (for ECoG) surface,
 +  and assign an electrode location by clicking on the surface. The electrode is
 +  placed on the triangulation itself.
 +  1020 - Starting from a triangulated scalp surface and the nasion, inion, left and
 +  right pre-auricular points, this automatically constructs and follows contours over
 +  the surface according to the 5% system. Electrodes are placed at certain relative
 +  distances along these countours. This is an extension of the 10-20 standard
 +  electrode placement system and includes the 20%, 10% and 5% locations. See
 +  "​Oostenveld R, Praamstra P. The five percent electrode system for high-resolution
 +  EEG and ERP measurements. Clin Neurophysiol. 2001 Apr;​112(4):​713-9"​ for details.
 +  Use as
 +    [elec] = ft_electrodeplacement(cfg,​ ct)
 +    [elec] = ft_electrodeplacement(cfg,​ ct, mri, ..)
 +  where the input mri should be an anatomical CT or MRI volume, or
 +    [elec] = ft_electrodeplacement(cfg,​ headshape)
 +  where the input headshape should be a surface triangulation.
 +  The configuration can contain the following options
 +    cfg.method ​        = string representing the method for placing the electrodes
 +                         '​volume' ​         interactively locate electrodes on three orthogonal slices of a volumetric MRI or CT scan
 +                         '​headshape' ​      ​interactively locate electrodes on a head surface
 +                         '​1020' ​           automatically locate electrodes on a head surface according to the 10-20 system
 +  The following options apply to the mri method
 +    cfg.parameter ​     = string, field in data (default = '​anatomy'​ if present in data)
 +    cfg.channel ​       = Nx1 cell-array with selection of channels (default = {'​1'​ '​2'​ ...})
 +    cfg.elec ​          = struct containing previously placed electrodes (this overwrites cfg.channel)
 +    cfg.clim ​          = color range of the data (default = [0 1], i.e. the full range)
 +    cfg.magtype ​       = string representing the '​magnet'​ type used for placing the electrodes
 +                         '​peakweighted' ​   place electrodes at weighted peak intensity voxel (default)
 +                         '​troughweighted' ​ place electrodes at weighted trough intensity voxel
 +                         '​peak' ​           place electrodes at peak intensity voxel (default)
 +                         '​trough' ​         place electrodes at trough intensity voxel
 +                         '​weighted' ​       place electrodes at center-of-mass
 +    cfg.magradius ​     = number representing the radius for the cfg.magtype based search (default = 3)
 +  The following options apply to the 1020 method
 +    cfg.fiducial.nas ​  = 1x3 vector with coordinates
 +    cfg.fiducial.ini ​  = 1x3 vector with coordinates
 +    cfg.fiducial.lpa ​  = 1x3 vector with coordinates
 +    cfg.fiducial.rpa ​  = 1x3 vector with coordinates
 +    cfg.feedback ​      = string, can be '​yes'​ or '​no'​ for detailled feedback (default = '​yes'​)
 +  See also <a href=/​reference/​ft_electroderealign><​font color=green>​FT_ELECTRODEREALIGN</​font></​a>,​ <a href=/​reference/​ft_volumerealign><​font color=green>​FT_VOLUMEREALIGN</​font></​a>,​ <a href=/​reference/​ft_volumesegment><​font color=green>​FT_VOLUMESEGMENT</​font></​a>,​ <a href=/​reference/​ft_prepare_mesh><​font color=green>​FT_PREPARE_MESH</​font></​a>​