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<table width="100%" summary="page for brain"><tr><td>brain</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Brain scan data</h2>

<h3>Description</h3>

<p> Functional magnetic resonance imaging measurements for a human
brain subject to a particular experimental stimulus. One slice of the image is
provided, described as a near-axial slice through the dorsal cerebral cortex.
</p>


<h3>Usage</h3>

<pre>
data(brain)
</pre>


<h3>Format</h3>

<p>A data frame with 5 columns and 1567 rows. Each row refers to one &lsquo;voxel&rsquo; of
the image. The columns are:
</p>

<dl>
<dt>X</dt><dd><p>voxel position on horizontal axis.</p>
</dd>
<dt>Y</dt><dd><p>voxel position on vertical axis.</p>
</dd>
<dt>medFPQ</dt><dd><p>median of three replicate 'Fundamental 
Power Quotient' values at the voxel: this is the main measurement of brain 
activivity.</p>
</dd>
<dt>region</dt><dd><p>code indicating which of several regions of the brain the voxel
belongs to. The regions are defined by the experimenters. <code>0</code> is the base
region; <code>1</code> is the
region of interest; <code>2</code> is the region activated by the experimental 
stimulus; <code>NA</code> denotes a voxel with no allocation.</p>
</dd>
<dt>meanTheta</dt><dd><p>mean phase shift at the Voxel, over three measurments.</p>
</dd>
</dl>



<h3>Details</h3>

<p> See the source article for fuller details.
</p>


<h3>Source</h3>

<p> S. Landau et al (2003)
&lsquo;Tests for a difference in timing of physiological response between two brain regions measured by using functional magnetic resonance imaging&rsquo;.
Journal of the Royal Statistical Society, Series C, Applied Statistics, 53(1):63-82
</p>


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