# SamSrf VII - Example pRF data set
This archive contains the minimally necessary files for running a pRF analysis
using SamSrf-7. Data were collected on a Siemens 3T Skyra using a multiband
sequence with 4x accelerated TR of 1s and isotropic 2.3mm voxels. The functional
data in the 'func' folder have already been motion-corrected and aligned to the T1.
The T1 is in the 'mri' folder. It has already been reconstructed in FreeSurfer
but *only the files necessary for SamSrf* use have been included here.
The stimulus was a series of sweeping bars, plus an interleaved blank period
in the middle and another at the end. You can view the apertures (see cookbook)
for details of the sequence. There were 6 runs, each with an identical sequence
of stimulus locations. Normally you would z-normalise and average the runs.
There is a NII file for volumetric data for each run, and there are also MGH files
for each run and each cortical hemisphere. These MGH have already been projected to
the cortical surface mesh using FreeSurfers's mri_vol2surf function. (See the shell
scripts included in the '*SamSrf/Utils*' folder for how this was done)
The standard approach is to use normalisation and averaging of runs. You can do
this with the *SurfaceProjection* tool. Either select the MGH or, if you want to
project the data to the surface using SamSrf's own routines, the NII files.
(The same can also be scripted using *samsrf_mgh2srf* and *samsrf_vol2srf*, respectively).
Go to the folder 'prf' before you do this so that the surface data files are created
there, right where you will need them. You can run the *Analyse_Prf* function to select
the created surface data file, and the occipital region of interest to start analysing.
A step-by-step guide might be added one day but that's it for now. Do check out the
Cookbook for further advice on how to run an analysis...
## Anything not working?
- Contact Sam: s.schwarzkopf@auckland.ac.nz
## Last updated: 04/08/2020
