NEUROSCIENCE

<p>Jan 01, 2013 02:05 PM

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human brain:

typical func MRI = 30,000 cortical voxels: &#160;say, each is 2 by 2 by 4 mm = 16 mm3

=&#62; &#160;total cortical volume of 480 cm &#160;= about 1/3 of total brain volume.

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suppose total number of neurons in human brain is about 86 billion (round off to 100B).

And say neocortex is 20% = about 20B neurons;

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total volume of neocortex = 480 * 1000 * mm3. &#160;

=&#62; &#160;40,000 neurons per mm3 &#160;in cortex &#160;&#160;(about right; &#160;I usu use 100,000 neurons per mm3)

depends on location.

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