When two stationary visual objects appear in alternating sequence, they evoke the perception of a single object moving back and forth between them. This is known as stroboscopic or apparent motion and ...

When astronomers talk about retrograde motion, generally they refer to the apparent motion outer planets make as Earth passes them while orbiting the Sun. Most of the time, all the outer planets ...

This is the fourth article in the Mind Matters series on the neuroscience behind visual illusions. Benjamin Franklin once said, “Never confuse motion with action.” But if motion is not action, then ...

In 350 BC, Aristotle reported seeing illusory movement after staring at a constantly moving stimulus. Later coined the "waterfall illusion," scientists are still investigating the properties of motion ...

THE AESTHETIC APPEAL of symmetry is obvious whether you are a child playing with a kaleidoscope or a Great Mogul emperor building the Taj Mahal as a monument to eternal love. That preference, as it ...