[Homer-users] AtlasViewerGUI - Probe Placement Variability Tool

[David Boas]

Chris Aasted provided a useful tool for AtlasViewerGUI for visualizing 
the variability of probe placement for a group of subjects.

Below is the description added to
http://homer-fnirs.org/faq/
Note that you can download a useful folder of data for testing this tool.

AtlasViewerGUI – probe placement variation

This tool was developed to visualize the optode positions obtained with 
a 3D digitizer and the variability of those optode positions for a group 
of subjects. While it has not been tested, it likely also works for 
visualizing the variability of optode positions registered to the head 
using the spring relaxation method. This tool is selected using the 
‘Tools -> Probe Placement Variation’ menu option. It will ask you to 
select the root directory of a group of subjects. Each sub-folder in 
this directory represents a subject and should contain an 
atlasViewer.mat file saved using the ‘File -> Save Viewer State’ menu 
option for each subject. This tool will create two figures. The first 
displays the each optode on the atlas head color coded for subject. The 
second figure displays the mean position of each optode and is color 
coded to show the standard deviation of the position across subjects 
with the scale given in mm units.

A demo group folder containing several subject sub-folders with the 
necessary information can be downloaded here to help you test the 
functionality of this tool.