What happens to the brain when you watch TV?

If you experience "mind fog" after watching television, you are not alone. Studies have shown that watching television induces low alpha waves in the human brain. Alpha waves are brainwaves between 8 to 12 HZ. and are commonly associated with relaxed meditative states as well as brain states associated with suggestibility.
While Alpha waves achieved through meditation are beneficial (they promote relaxation and insight), too much time spent in the low Alpha wave state caused by TV can cause unfocussed daydreaming and inability to concentrate. Researchers have said that watching television is similar to staring at a blank wall for several hours..
I enjoy watching television on occasion, and this article is not meant to suggest that people should never watch TV. However, it is only fair that people understand what happens to the brain each time it is exposed to television.
In an experiment in 1969, Herbert Krugman monitored a person through many trials and found that in less than one minute of television viewing, the person's brainwaves switched from Beta waves-- brainwaves associated with active, logical thought-- to primarily Alpha waves. When the subject stopped watching television and began reading a magazine, the brainwaves reverted to Beta waves.
One thing this indicates is that most parts of the brain, parts responsible for logical thought, tune out during television viewing. The impact of television viewing on one person's brain state is obviously not enough to conclude that the same consequences apply to everyone; however, research involving many others, completed in the years following Krugman's experiment, has repeatedly shown that watching television produces brainwaves in the low Alpha range.