Hi all,<div><br></div><div>Some work my colleagues and I did investigating how many subjects should be included in a study has been recently published in Human Brain Mapping (<a href="http://www.ncbi.nlm.nih.gov/pubmed/22807270">http://www.ncbi.nlm.nih.gov/pubmed/22807270</a>). The paper should be freely available on pubmed central fairly soon if you don&#39;t have access to Human Brain Mapping early view. Or I can send you a copy.</div>

<div><br></div><div>I&#39;ve provided some instructions on how to carry out a similar analysis using your own Freesurfer-processed control data here: <a href="http://www.brain.org.au/software/cortex/power">http://www.brain.org.au/software/cortex/power</a></div>

<div><br></div><div>The R package provided at the above link contains a function &quot;load.mgh.R&quot; which can be used to load mgh surface files into R &amp; do whatever sophisticated statistical analysis takes your fancy.</div>

<div><br></div><div>Let me know if you&#39;ve got any questions.</div><div><br></div><div>Best wishes</div><div>Heath</div><div><div><br></div>-- <br>Heath R. Pardoe, PhD<br>Florey Neuroscience Institutes<br>Melbourne Brain Centre<br>

245 Burgundy Street, Heidelberg 3084<div>Australia<br>Phone: (+61 3) 903 57053<br>Email: <a href="mailto:h.pardoe@brain.org.au" target="_blank">h.pardoe@brain.org.au</a></div><br>
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