w11 guest Baene cognition and tumors Flashcards
how to research on structural connectivity
look for anisotropy in diffusion
Molecules move from parts with higher to parts with lower concentration. If there are no boundaries, it happens in every direction. Isotropic diffusion - the same in every direction. Cell walls and myelin impede such motion → anisotropic diffusion: different diffusion coefficients along different directions
how to research on functional connectivity
you have to see which parts function together. Therefore you look at the correlation of time series of the regions.
Example: resting state connectivity
how was this labeled?
they compared the resting state data with the data from particular cognitive tasks and labeled the similarity with the task related activity
which one is related to the executive functions?
Frontoparietal resting state control network
Onco-functional balance
process of deciding how much tissue around tumor to remove. If you remove only the heart of the tumor you save more brain function, but the tumor is more likely to grow again, and if you remove all the healthy tissue around the tumor, then the tumor is less likely to return, but you lose a lot of brain function
how to determine the extent of resection of the brain tumor?
They stimulate a region and see if it functions as intended. For motor - obviously, if something moves. For other parts - the patient performs cognitive tasks, and the surgeons see if the stimulated part becomes impared or there is no difference. IF it becomes impared, the task is not complete, it means that it’s healty tissue and it shouldn’t be removed.
They use white matter trackts as boundaries to stop the surgery.
FAT
Fronto-aslant track
connects the posterior parts of the inferior frontal gyrus and the superior frontal gyrus
they researched on one case first, a patient with a tumor interfering with FAT, and then on a number of patients they researched on the relationship between the proximity of a glioma to FAT and executive function, and then they discovered that it’s involved in executive function: shifting attention, continuous performance, phonemic fluency
relationship between FPN and DMN
so between frontal-parietal network and default-mode network
the DMN should deactivate when FPN is active. So the more dissimilarity between their function - the better the overall function
FPN/DMN task-evoked reconfiguration – cognitive performance
Cognitive performance in brain tumor patients is associated with the capacity to reconfigure the FPN during a cognitive task
there is no one to one map between structural connectivity and functional connectivity, and there is a huge interindividual variability
you can try virtual neurosurgery. they used deep learning to predict functional connectivity based on structural connectivity, so on tractography, and they achieved the link between the predicted and the actual functional connectivity was r = 0.9!
And de Baene is working on providing neursurgeons with a map based on this deep learning simulation of which structural areas are more or less safer to remove in order to not damage the function
