Hello everyone,
I am an undergraduate using brainstorm for the first time to analyze some existing EEG data so please excuse my very limited understanding. Context: we have a study where we had people complete a task while wearing a 256-electrode EGI cap (water-based), and we rendered a model of most of the brain using brainstorm.
For a possible poster presentation I am trying to investigate if there were any activation differences in the cerebellum during the task. I am aware that there is a cerebellum mask we can use to construct the models, but we did not use it the first time around since it was not a region of interest initially. We are trying to avoid creating new models if possible because it takes so long on our lab computer. Would this be the only way to use the filter, or is there another way we can add the cerebellum mask to our existing model?
Thank you so much, please let me know if there is any other info that would be useful!
If the initial source space did not include the cerebellum, incorporating it now will be complicated. There is a possible solution, but it will be time-consuming in terms of scripting and data manipulation. Therefore, I recommend recomputing the activation to include the cerebellum. This approach will be much simpler and safer, reducing the risk of errors in data manipulation.
Thank you! So we ended up recomputing the model for one participant with what we thought was a cerebellum mask added, but the model did not show any of the activation. Do you know what specific settings we could use to rerun the models?
When using the Default anatomy or if the imported anatomy was segmented with FreeSurfer, Brainstorm generates a surface called cortex_cereb_17005V which includes the cortical surface + cerebellum surface.
Before computing the head model, set this surface a default cortex (shown in green).
Now the head model computation will use this surface.
Source space:
Cortex surface: Source dipoles will be located on the vertices of the cortex+cerebellum surface
MRI volume: Source dipoles will be located inside the cortex+cerebellum surface
Thanks for your reply! This is what we already tried, and while it did add a cerebellum to the head model, it does not show the activation. Any idea why this might be?
We actually ended up having luck, thank you! It appears that we are actually getting cerebellum activation with this model, I just want to run it by the pros first to be sure before I start doing any analysis. I attached the default anatomy, head model settings, atlas, and resulting image. I apologize for awkwardly compiling the images, I can only upload one as a new forum member. Thanks in advance!
It looks good the cortex with cerebellum is set as default, and the head model is computed with that cortex surface. After that just follow the tutorial on estimating sources:
Once you have compute the sources, double-click the result, it will automatically display the brain activity in the source space that was compute, in your case it will be the cortex+cerebellum
