Grey’s Anatomy – Brain Tracking Denny
Regular readers of these posts will recognize a common theme that takes place nowadays in some of the most popular TV shows. I like to call it the "Let’s take a little bit of theoretical science and make it reality" theme. The latest practitioner of this theme is Grey’s Anatomy.
I have to admit, I hesitated to write this one. It meant I would have to admit that I watched the show. I’ll use my wife as an excuse. She loves it and I just watch to fit in. 
In the episode "What a Difference a Day Makes", Izzie becomes convinced that she has a brain tumor because she keeps having visions of her late fiance’ Denny. They don’t find any evidence that the tumor exists. Dr. Shephard comes up with the idea of hooking her up to an EEG machine that will measure her brain waves. He figured that if she starts having the visions, that he’ll be able to use the EEG readings to locate the tumor. The theory is that if she starts to have a vision, they will see increased brain activity at one exact point in the brain and that would be the location of the tumor. Low and behold, it worked like a charm. They not only located the tumor, but were able to go in and remove it as well.
I’ve got Call Bull on that one. There are several problems with this. They are right about one thing; the vision would more than likely result in additional brain activity. After that, the Bull begins! First of all, if tracking thoughts were that easy we’d have mapped the brain decades ago. The brain is a neural-network. There is no single point where a thought originates; it is spread out across the brain. That’s why people are often able to recover from brain injuries. No single point in the brain has complete control of anything.
The second Bull factor is that even if the vision came from a single part of the brain, the lone thought would not create a strong enough electrical current to stand out from all the other brain functions underway. It would get lost in all the other "noise" talking place. You can bet that when the vision started, Izzie’s stress level shot up. That would have created a whole flood of activity in all parts of the brain.
And finally, if the vision could be isolated and measured it still wouldn’t lead them to the tumor. The tumor itself isn’t creating the vision. It’s just changing the chemistry and connections in the brain to make way for the vision. Some other part of the brain is actually making her see Denny.
Once again…WeCallBull. I’ll admit I’m not a brain surgeon and could be totally wrong about all of this. Feel free to comment and prove me wrong.
