Monday, October 29, 2007

Brain waves and virtual reality

Never expected this technology will come out so fast! Last day, I was going through the MIT news and came across this headline reading: "MIT research helps convert brain signals into action". Dr. Lakshminarayan Ram Srinivasan, a post doctoral researcher at MIT, has invented a new neuroprosthetic algorithm to translate thoughts into computer actions! This new technology can control the characters of Second Life, without even moving a single body muscle... all just by thoughts!

Now my blog just could have ended by the above paragraph! But then I just thought I should write a bit more for those curious minds to know more about how such a technology might work. Well, I am not a neurologist by any means, but the ideas on the brain, the intelligence and the concept of consciousness has been confounding me since a long time. There have been numerous news articles on technologies like this before... but I found this one to be different since it uses neuroprosthetics. Neuroprosthetics deals with using electronic devices to interface with the brain, without actually opening the cranium! Well, such a non-intrusive method seem actually appealing to a non-medical person like me, where-in you can just communicate with the brain without actually opening it up and playing with the mess :) . I have read in the past over ideas on using the BCI to toggle light bulbs or Dr.Kevin Warwick's strange experiments in cybernetics of interfacing the nervous system with an integrated circuit, but then this one is compelling.

So what are brain waves? Well, you know our brain is a complicated electro-chemical circuit, with millions of neurons wired all across. Thus its just natural to imagine that they must be associated with electromagnetic waves too...and these are the brain waves. Fundamentally they are of four different frequencies: beta(13-38Hz), alpha(8-13Hz), theta (4-7Hz) and delta (less than 4Hz). Studies have shown that there are many other kinds of brain waves too... like the gamma waves (40-100Hz), the Sensory motor rhythm (SMR) waves etc, but for our current discussion I guess the first four are good enough, since they characterize the ones commonly seen.

So beta waves are produced when the brain is in active work, like in a conversation, or in high beta when in a debate! When a person is tired after experimenting with the beta state, he moves into the alpha brain wave state. They are basically with lower frequency and higher amplitude. Usually people taking the "art of living" puts their brain into this state :). The energy of activation in this state is low.

Next comes the theta state, which is basically associated with creativity. Whenever you day dream, or think laterally or imagine stuff, then theta waves take over... I have noticed that I come across a lot of ideas when I travel... This state is considered to be a positive mental state and the mind goes unrestricted in searching for creative things. Finally the delta waves are those which occurs when the brain goes to sleep... these are the slowest of the waves with the greatest amplitude.

So at any point of time, a human brain will be producing a mix of all these waves. But then the part of decoding the waves back to what he is thinking is just another big challenge. So if what the article stated above comes out successful, then its not very long when emotions of people can just be traced with gadgets and thus thoughts are never personal again! Well, again its interesting to see what role such inventions play in defining what consciousness "really" means!


10 comments:

Biplab Chattopadhyay said...

While reading this article I found only beta rays spreading here and there. :)

Nice article dear.

Naresh Chandrasekaran said...

Bheja Fry :P

Amitabh Saikia said...
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Amitabh Saikia said...
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Amitabh Saikia said...

Thought provoking!! Would be a devils advocate here. Science and Technology is dual-sided sword. But as an avid devote to science and technology like you, should not we also think of possibilities that it can bring. Human mind had been less understood since ages. Can this understanding about the waves bring more light to how we think. Can we affect lives?

One thing that comes to my mind is language. I always felt language is one of the biggest barrier in human communication. We understand so less as we have tagged experiences with words, which differs based on every human being that we interact. I would love to see, if I could bring eyes to a blind by developing some kind of telepathic communication so that each of us can experience from the eyes of others. Some of us see things in an interesting way.

Nikhil said...

Interesting! 2 observations.
Cognition in humans aside, machines show much more promise of simulating human thinking outwardly sometime soon. I work in the area of cognitive radios, and that sometimes makes me think of cognition in general. If we can make radios think logically like a human, but stripped of all the biases, instinctive behaviors etc, won't that be much better than blindly aping ( trying to ) everything that a human brain is capable of?

BTW Have you read the Emperor's New Mind by Penrose?

Nikhil said...

As to BCI, we have a significant effort in that direction, in which one of my labmates is involved too. So, I get to see how they wire up the neurons and perform PCI and ANN and other stuff to process the neuronal signals to control human actions.

Anonymous said...
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vani murarka said...

what is the article from MIT that you are referring to - which prompted you to write this blog post? can you provide a link to that article? also, what is BCI?

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