Re: is there any way to make the human brain reconize non oraganic body parts

Dear No Name Entered,

So you are looking for the Holy Grail of prosthetics!  I can guarantee it 
will be a long hard road, but one that needs smart, inventive people and 
the rewards could be fantastic.  Since you are doing a report, I will try 
to find web sights that will give you valuable information as well as some 
of what I know off the top of my head, but I may not remember the source.

First, the brain.  An extremely complex organ that we still know little 
about.  We do know that all brain signals are electric in nature and are 
therefore, theoretically, measurable.  But it would be like marking a honey 
bee with a white dot and sending it into a hive and listening for it's 
buzz.  Be pretty difficult with thousands of other buzzes occurring at the 
same time!  Now if we knew the particular buzz our bee made and could 
filter out the rest and knew where our bee likes to hang out, the job would 
be easier.  There is some work along this line that I know of.  You may 
have heard about artificial eyes lately.  The ones I know of work by small 
receptors that pick up hues and shades and are transmitted to small silicon 
chips that are formed in the shape of a small nail bed (or something 
similar.  Imagine an array of sharp silicon spires on a small wafer).  
These are jabbed into the optical region of the brain, and each spire is 
connected to one receptor.  When one receptor picks up color or light, it 
sends a signal to the spire which in turn activates a neuron ( or a couple 
of neurons) in the optic area of the brain.  An array of receptors 
activates an array of spires which activate an array of neurons.  The 
resulting image is like a very low resolution picture with some color and 
shading.  (Think of what your monitor would look like with 20x20 pixel 
resolution instead of 600x800 or more!)Some of the problem is getting the 
receptors and electronics small enough, and the other is getting the 
silicon spires narrow enough.  With the latest photoimaging processes you 
still are hitting a number of neurons with one spire.  The other is getting 
them to the right neurons.  There isn't a way to single out individual 
neurons, just areas.

I tried to find some information on the talk that I had heard on the above 
info but found none.  (The talk was really about micro-silicon part 
production, the eye thing was just an example).  However, I did find three 
excellent articles on artificial retinas that focused on implanted chips 
that directly excite the ganglion of the optic nerve.  (My above 
explanation was for optic nerve damaged patients).  Again, there are 
problems with the fact that they still can't specify which ganglion they 
excite, and how many!  The first three articles are on essentially the same 
concept, and the fourth is a very exciting hybrid implant using 
artificially cultured neuron cells!  Probably the most advanced work in 
non-organic to nerve interaction is in retina development.
 http://www.optobionics.com/
 http://www.coe
.ncsu.edu/news.releases/liu.retina.html
 http://rleweb.mit.edu/retina/
 http:
//www.cmplx.cse.nagoya-u.ac.jp/research/retina/index.html

Second, the nerves and external limbs.  First off, I will take offense at 
your statement that "anyone can throw a few pipes together with pivot 
points and make it mobile with a small engine."  As an ME I can assure you 
it is not that easy.  Mobile power (batteries are heavy and run down 
quickly), strength vs. speed and how to control them, and realistic 
movement are all very complex engineering problems associated with electric 
arm design.  But I will grant you, those are easier than what you are 
interested in doing!  One of the best examples that I am familiar with is 
the Utah Arm, which was developed at the University of Utah.  The idea of 
this arm was to use metal conductors and a signal amplifier to detect the 
electrical output from remnant muscles in the stump of the arm.  This means 
that a mid-humerus amputation usually leaves some of the biceps and triceps 
muscles.  These are still controlled by the amputee.  Now just like the 
heart has an electrical signal that can be detected in an EKG, these 
muscles, when contracted, give of a small electrical signal. This is 
amplified by the metal receptors which turns on the appropriate motor for 
arm movement.  Motion Control is the current manufacturer and the arm info 
can be found at http://www.utaharm.com// .  It isn't a 
great sight but will 
give you some info and some good pictures and perhaps some links.

Good luck with your report.  I hope I shed some light what you were asking 
about.  If you have physiology (how the body works) questions, you might 
need to reference some medical books (Fundamentals of Physiology: Second 
Edition by Lauralee Sherwood from West Publishing Co. is a great beginning 
book on how the body works.  You librarian may know how to get it on loan 
for you).  If you have more questions or would like to pick my brain about 
school, careers, etc. I would be very willing to talk to you about it as 
your goal is what I originally started out to do as well (and may still 
do!).  E-mail me any time if you have questions at bradk@jymis.com.  Again, 
best of luck and keep following your dream!
BK