Daydreams On My Eyelids

It's been a week since my last Peter Gabriel soundcheck (rehearsal you have to pay top dollar in order to see) and concert.  One of my favorite things about attending Peter Gabriel soundchecks and concerts is that I continue to see it when I close my eyes.  It's as if Peter somehow burned snapshots of himself into my retinas.  Sadly, this fades after a few days.

Have you ever noticed this?  Images seeminly on your eyelids?  You just close your eyes and you see a kind of photo negative of these images.  Not for Peter Gabriel, specifically, but for any object you see a lot in one day.  The images are far more noticeable in a dark room.  It can't be only me this happens to.

It's probably the same phenomenon as afterimage, an optical illusion where you see photonegative images on your eyelids.  Only afterimages tend to happen immediately after looking at something.  They usually don't happen for days afterward.

There is a vision problem called palinopsia where people see afterimages all of the time, but my after concert images tend to happen only when my eyes are closed in a dark room and becomes more intense when I start to get drowsy. They do not occur in daytime or to the point where I can't find my way around. 

I wonder if it's a form of daydream or related to hypnogogic sleep.  These images can be manipulated, but doing so effectively can be tricky.  Trying to manipulate the images so I see what I want to see requires concentration -- but not so much concentration as to wake me up.  If you've ever practiced meditation, you are already familiar with the concept of the empty mind.  You need to watch the objects on your eyelids passively in order to keep the right balance of groggy to wakefulness so that you can enjoy the eyelid show without waking up or falling entirely to sleep.

Image from Wikimedia Commons