• Corpus ID: 18516145

On the geometric structure of fMRI searchlight-based information maps

@article{Viswanathan2012OnTG,
  title={On the geometric structure of fMRI searchlight-based information maps},
  author={Shivakumar Viswanathan and Matthew Cieslak and Scott T. Grafton},
  journal={arXiv: Neurons and Cognition},
  year={2012}
}
Information mapping is a popular application of Multivoxel Pattern Analysis (MVPA) to fMRI. Information maps are constructed using the so called searchlight method, where the spherical multivoxel neighborhood of every voxel (i.e., a searchlight) in the brain is evaluated for the presence of task-relevant response patterns. Despite their widespread use, information maps present several challenges for interpretation. One such challenge has to do with inferring the size and shape of a multivoxel… 

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