Traditional cameras use either charge-coupled devices (CCDs) or complementary metal oxide semiconductor (CMOS) chips, which capture images on a grid of millions of pixels.

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When light strikes a CCD, it excites the electrons in the chip, creating a grid of charged elements or pixels (for picture elements).

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To process the MRI data, a computer overlaid on Pickens' brain a virtual three-dimensional grid of 50, 000 cubes called voxels (a word hinting at volume and pixels).

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