Christine Ahrends
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cahrends.bsky.social
Christine Ahrends
@cahrends.bsky.social
100 followers 140 following 8 posts
Neuroscientist, Junior Research Fellow at Linacre College/FMRIB, University of Oxford Interested in human neuroimaging, brain dynamics, ML & biobanks
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I've had a chat with Chris from #TheNakedScientists for the @elife.bsky.social podcast about our new paper "Predicting individual traits from models of brain dynamics accurately and reliably using the Fisher kernel": elifesciences.org/podcast/epis... #neuroskyence
Read the short and sweet version of our new paper about predicting from brain dynamics, featured in elife digests magazine: elifesciences.org/digests/9512... #neuroskyence
The intuition is that our approach uses a useful projection - like shining a light on an object and looking at its shadow
Predicting individual traits from dynamic brain activity
A combination of machine-learning techniques and more traditional modeling approaches can use the unique patterns of brain activity that evolve over time to predict traits such as age and cognitive ab...
elifesciences.org
The whole workflow, from fitting the HMM to constructing the kernel and predicting from it, is part of the GLHMM toolbox in Python: github.com/vidaurre/glhmm and the old HMM-MAR toolbox in Matlab: github.com/OHBA-analysi.... Find all code to replicate the paper in github.com/ahrends/Fish....
GitHub - vidaurre/glhmm
Contribute to vidaurre/glhmm development by creating an account on GitHub.
github.com
The HMM-Fisher kernel approach has no issues here, but we found that several other kernels were problematic in this respect. The key here is the projection: We found that, like for static FC, the right projection leads to more accurate and more reliable predictions.
Beyond accuracy, we thought a lot about reliability. If we run the model again, using standard CV and regularisation with new randomised folds, do the results change dramatically? And 2. Are there single cases where a prediction is so terrible that it would be useless in real-world applications?
The HMM-Fisher kernel approach allows leveraging the entire rich description of dynamic functional connectivity and amplitude changes to predict, e.g. an individual’s cognitive test scores or demographics. It is also computationally efficient and flexible to be used with various other models.