Table A1.

Key fields within the Matlab structure representing a pRF model

Field	Description
M.pE	Prior mean (expectation) of each parameter
M.pC	Prior covariance of the parameters
M.IS	Name of the pRF model function to use
Y.y	Matrix of timeseries data against which to estimate the model
xY.XYZmm	Coordinates (mm) of each timeseries in the brain
U	[1 x T] structure representing the T stimuli displayed during scanning, including onsets, durations and coordinates of stimulated pixels
Ep	Estimated parameters for each voxel
Cp	Estimated covariance of the parameters for each voxel
Eh	Estimated log precision of the noise
F	Variational free energy (approximate evidence) of the model for each voxel