We have recently found an issue that needs to be known, with regard to importing BrainMaster EDF files into NeuroGuide. This is true for EDF files written by any of our software, 1.5.9 as well as the 4.0 BrainAvatar software. To summarize, in the latest versions of NeuroGuide, users who are importing EDF files must pay attention to select "LE" as the chosen reference when reading in the file, in the popup list that appears automatically. If this is not done, the reference will default to "A1" and the resulting analysis and maps will be incorrect. This is a change in the NeuroGuide behavior which, while it is not technically an error or bug, now requires users to pay attention to this detail and make an extra step when they import files.
The origin of the concern is due to the fact that NeuroGuide used to default the reference selection to "LE" which is the reference for the 10-20 sites, and the user could simply click "OK" on the popup list after selecting the file for import. Most recently, in the last version or two of NeuroGuide, this selection defaults to "A1" because that is the reference for the last channel, which is "A2-A1." While it would seem reasonable to select the last used reference as the default, that is not the correct reference for the BrainMaster EDF files generally. We have contacted ANI, and they do plan to change this default back to the "LE" on the next release. However, for the current releases, it will be necessary to always select the "LE" reference by clicking on it before clicking on "OK."
If the A1 reference is used by accident, the result is that the maps are done as if A1 was the reference, and the power maps and connectivity maps all show erroneous power and coherences, which will result in incorrect interpretations. One telltale sign is if you suddenly see a lot of high beta hypercoherences, particularly involving T3 or other left-side sites.
SO: Please make sure you select "LE" as the reference when you import EDF files from BrainMaster into NeuroGuide.
As a second point, we want to make sure users understand that the Lexicor file format option ".dat file" is not intended for import into NeuroGuide. If .dat files are imported into NeuroGuide, they will be processed as if they came from a NeuroSearch 24, and the compensations will be wrong. The powers will appear to be about 1 standard deviation high, while the relative powers, and connectivities will be relatively correct. But do not import Lexicor (.dat) files into NeuroGuide. EDF files are the only files from BrainMaster software that should be read into NeuroGuide.
We appreciate everyone's diligence and attention to these details. We work hard to make sure that our interoperation with ANI and other 3rd party developments work correctly, but it sometimes requires user attention to make sure that best practices are always followed.
As a final note, we would like to emphasize that we remain strongly committed to supporting ANI and NeuroGuide, and have every intention to continue, and grow, our level of interoperation and support of ANI products. We have always had a cordial and professional relationship with Bob Thatcher and his team, and it is a pleasure to work with people who value scientific integrity and service to the community. When issues like these arise, we endeavor to address them with open communication and a collaborative spirit.
BrainMaster Technologies Inc honors ANI's policy of one permanent license per computer. This includes one annual backup license.