In response to Jenny McCarthy making the rounds of media outlets to promote he new book about her experiences with and opinions about her son's autism Autism Diva has posted some fascinating information about vision and the human brain. She says some stuff about Jenny McCarthy too which you can peruse at your leisure.
Anyway, the stuff about vision and the brain reminded me of a cool little phenomenon I discovered sometime back. To experience this phenomenon you will need:
- A brightly lit room with a dimmer switch at night time.
- A mirror, the bigger the better.
- Any corrective eye gear you normally wear.
Make sure that there is not a lot of extra light getting into the room. Depending on the size of your mirror either place it where you can see yourself in it and still reach the light switch or simply hold it in you hand at arms length. Start with the lights all the way on then slowly turn them down. Then slowly turn the lights back up again. You should be able to perceive the slight adjustments of your eyes to the changing light levels.