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In more 'joe sixpack'-terms. After you move your eyes fast, they are unable to collect information for a fraction of a second. When the eyes comes back 'online' the brain collects motion-information for an equal fraction of a second, and extrapolates the information backwards to create what things should have looked like and fills this fabricated visual information into your memory. Since the needle (or digit) didn't move while the brain was collecting info for the extrapolation, it won't be able to predict that it moved in the past either.