The Internet – that strange place where sound moves faster than light
I was giving a live web presentation today to demonstrate some software. I was using Blackboard Collaborate, the offspring of the mating of Elluminate and Wimba, a very nice platform for this purpose.
As sometimes happens when using web conferencing software like this, the video part of the live demostration was taking longer to arrive in the participants’ broswers than the audio part. The amount of data that is needed to support live streaming video is much greater than the amount of data that is needed to support live streaming audio, and therefore sometimes the pictures follow the words.
It struck me that this creates a strange illusion on the web, an illusion that sound is faster than light. In the physical world, of course, light is faster than sound. Go to any fireworks display and witness the phenomena for yourself.
Learning is not enhanced when our virtual world does not match what we expect to see in our physical world. Audio and images out of sync creates a cognitive dilemma for the brain that has to work harder to try to match up content that is out of sequence, and reconstruct it in the correct sequence. This uses up scarce resources in working memory that would otherwise be used to process the content of the activity, not the modalities of the media.