This document decribes how to install the new version of Unwarp. Since Unwarp is a part of main SPM2 this distribution will (eventually, when bugs are fewer) be part of the general SPM updates. Meanwhile we recommend the following method for installing the update. 1. Create a local directory, e.g. /usr/local/'whatever'/Unwarp_updates 2. Download the Unwarp_ddmmyy.tar.gz file into that directory 3. Unzip and untar, ..]$ gunzip Unwarp_ddmmyy.tar.gz ..]$ tar -xvf Unwarp_ddmmyy.tar on a linux machine. 4. If you are on a Macintosh, or some other exotic brand, you will need to compile spm_dilate_erode.c. It should work to simply cd to /usr/local/'whatever'/Unwarp_updates, start Matlab and at the Matlab prompt type >> mex spm_dilate_erode.c 5. Make sure that /usr/local/'whatever'/Unwarp_updates is included in your Matlab path ahead of your main SPM distribution. 6. If (very optional) you want the help in the SPM graphical help (for the "Realign & Unwarp" button) to reflect Realign and Unwarp you should rename mod_spm.m spm.m and put it in your main SPM distribution directory. DONT rename it and leave it in the Unwarp_updates directory! Good luck Jesper