Post on 31-Mar-2015
SVD single voxel analysisFrank Leone, Ivan Toni, Pieter Medendorp
Location = direction * amplitude?
vs
Singular value decomposition
Previous work: Location = X * Y (auditory domain)
Pena & Konishi, 2001
Previous work: Eye vs Hand relative tuning
Pesaran et al, 2006
Previous work: Eye vs Hand relative tuning
Pesaran et al, 2006
Closer inspection of fields
Roughly Gaussian
Correlation preferred amplitude and field width (?, in progress)
Extensions / applications
Test different representations:• X – Y• Multiplication vs addition
Test separability in general, of any two multivalue effects
More general: fit functions through your single voxel t-values, instead of making simple contrasts
T values or beta’s?
Conclusion
There is more than meets in the eye in single voxels
Can fit functions to your t-values
Can use SVD to test separability