KCCA Feature Selection for fMRI Analysis
David Hardoon, John Shawe-Taylor and Ola Friman
Not intendent for publication.
We use Kernel Canonical Correlation Analysis (KCCA) to infer brain activity in functional MRI by learning a semantic representation of fMRI brain scans and their associated activity signal. The semantic space provides a common representation and enables a comparison between the fMRI and the activity signal. We compare the approach against Canonical Correlation Analysis (CCA) and the more commonly used Ordinary Correlation Analysis (OCA) by localising “activity” on a simulated null data set. We also compare performance of the methods on the localisation of brain regions which control finger movement and regions that are involved in mental calculation. Finally we present an approach to reconstruct an activity signal from an “unknown” testing-set
fMRI scans. This is used to validate the learnt semantics as non-trivial.