# 4. (optional) Surface Reconstruction

This is an optional step to perform surface reconstruction. One approach uses the Computational Anatomy Box (CAT12), which is an extension of SPM12. CAT12 uses a completely different segmentation approach. Read more on [their website](https://www.neuro.uni-jena.de/cat/). Another approach uses Freesurfer. See [their website](https://surfer.nmr.mgh.harvard.edu) for more details.


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