Wherever I see the color ’4,’ it glows orange in my mind’s eye. I still see it as black on a white page but I know, somewhere deep down, that it’s really orange. It’s the same way I know that 7 is ...

Carol Steen's father once corrected her about the color of the number five. That number is yellow, she told him. "And my father said, 'No, it's yellow ocher.'" Her dentist has done a root canal ...

Ever caught a whiff of the color blue? Or tasted a symphony? If that sounds completely bonkers to you, you’re in the majority. But for a small slice of humanity, these cross-sensory experiences are ...

Research shows that the unique sensory experience of “synesthesia” can be acquired through training, and leads to a variety of mental benefits. Vincent van Gogh, Richard Feynman, Stevie Wonder. Each ...