Ensembling Brain Regions for Brain Decoding

Alkan, Sarper
Yarman-Vural, Fatos T.
In this study, we propose a new method which ensembles the brain regions for brain decoding. The ensemble is generated by clustering the fMRI images recorded during an experimental set-up which measures the cognitive states associated to semantic categories. Initially, voxel clusters are formed by using hierarchical agglomerative clustering with correlation as the similarity metric. Then, for each voxel cluster, a support vector machine (SVM) classifier is trained to estimate the class-posteriori probabilities. Lastly, the class-posteriori probabilities are ensembled by concatenating them under the same feature space, which are then used to train a meta-layer SVM for the final classification of the cognitive states.


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Citation Formats
S. Alkan and F. T. Yarman-Vural, “Ensembling Brain Regions for Brain Decoding,” 2015, p. 2948, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/66015.