Researchers at the University of Texas, in Austin, have been looking into the way the brain deals with 3D motion. They studied people watching 3D visualizations while lying motionless for 1-2 hours in an MRI (magnetic resonance imaging) scanner. They found that the images were processed in parts of the brain just behind the left and right ears called MT+. The area had been thought to be only responsible for 2D motion (up and down, left and right). Because the view from one's left and right eyes is different the brain can use the disparity in these images over time to calculate movement; processing which comes together in the MT+ region.
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