Why Do We Get 'Dorsal Fingers' When Holding Our Phones?

Imagine your fingers are little birds flying just above the glass of your phone. When you scroll through pictures or read messages, sometimes they look like they are floating in mid-air instead of touching the screen. It is a weird trick your eyes play on you.

Your brain uses two different systems to see where things are. One system looks at the big picture and tells you "my hand is over there." The other system zooms in very close to check if my finger is touching the glass or hovering a millimeter above it. Usually, these two messages agree perfectly.

When you stare intently at your phone screen for too long, the "zoomed-in" system gets tired and confused. It stops sending clear signals about how far away your fingers really are. Your brain guesses wrong and thinks your fingers are higher up than they actually are. This is called dorsal fingers.

It goes away quickly! You can fix it by blinking, looking at something else for a second, or wiggling your hand. Wiggling gives your brain new clues about where your fingers really are. So next time you see your thumb floating like a ghost over YouTube, don't worry. Your eyes are just taking a little nap.