Sunday, April 23, 2006

Brain in a Dish Flies

This picture documents an important event in 1911.
But hear this! Less than hundred years later...
A University of Florida scientist has created a living "brain" of cultured rat cells that now controls an F-22 fighter jet flight simulator.

Thomas DeMarse, a University of Florida professor of biomedical engineering, placed an electrode grid at the bottom of a glass dish and then covered the grid with rat neurons. The cells initially resembled individual grains of sand in liquid, but they soon extended microscopic lines toward each other, gradually forming a neural network — a brain — that DeMarse says is a "living computational device."

"We grow approximately 25,000 cells on a 60-channel multi-electrode array, which permits us to measure the signals produced by the activity each neuron produces as it transmits information across this network of living neurons," DeMarse told Discovery News. "Using these same channels (electrodes) we can also stimulate activity at each of the 60 locations (electrodes) in the network. Together, we have a bidirectional interface to the neural network where we can input information via stimulation. The network processes the information, and we can listen to the network's response."

The brain communicates with the flight simulator through a desktop computer.
Read the whole story here!


Since 1986 and K. Eric Drexler´s classic The Engines of Creation (EOC) the meme of selfassembling machines has been a source of imagination and horrifying ideas:
This is Drexler himself (EOC):
"Genetic evolution has limited life to a system based on DNA, RNA, and ribosomes, but memetic evolution will bring life-like machines based on nanocomputers and assemblers. Assemblers will be able to build all that ribosomes can, and more; assembler-based replicators will therefore be able to do all that life can, and more. From an evolutionary point of view, this poses an obvious threat to otters, people, cacti, and ferns - to the rich fabric of the biosphere and all that we prize. (...)
Replicators can be more potent than nuclear weapons: to devastate Earth with bombs would require masses of exotic hardware and rare isotopes, but to destroy all life with replicators would require only a single speck made of ordinary elements."

For those of you who have been reading Drexler merely as science fiction, the following article written by Zyvex LLC Research Scientist Robert A. Freitas Jr. may be illuminating:
"...the possible dangers posed by future technologies such as artificial intelligence, genetic engineering and molecular nanotechnology have made it clear that an intensive theoretical analysis of the major classes of environmental risks of molecular nanotechnology (MNT) is warranted. No systematic assessment of the risks and limitations of MNT-based technologies has yet been attempted."

Freitas uses the term "global ecophagy" for the risk that self-replicating nanorobots capable of functioning autonomously in the natural environment could quickly convert that natural environment (e.g., "biomass") into replicas of themselves (e.g., "nanomass") on a global basis..."

"The maximum rate of global ecophagy by biovorous self-replicating nanorobots is fundamentally restricted by the replicative strategy employed; by the maximum dispersal velocity of mobile replicators; by operational energy and chemical element requirements; by the homeostatic resistance of biological ecologies to ecophagy; by ecophagic thermal pollution limits (ETPL); and most importantly by our determination and readiness to stop them."

After a thorough analysis Fritas ends up with the conclusion: "The smallest plausible biovorous nanoreplicator has a molecular weight of ~1 gigadalton and a minimum replication time of perhaps ~100 seconds, in theory permitting global ecophagy to be completed in as few as ~104 seconds.
In short, the paper calculates that the maximum speed that self-replicating nanobots could eat the Earth is 2.78 hours. (This was calculated by Jurvetson, here.

Read it your self at!


Picture: Max-Planck-Institute for Biochemistry, Department of Membrane and Neurophysics

Anonymous sent me a comment with a link to this story at the Discovery News. "April 19, 2006— A rat nerve cell attached to a semiconductor chip has exchanged a signal with the chip, an achievement that could lead to organic computers that process information like a brain, say researchers."

If you want to see the meaning of this innovation you should read Kevin Kelly's WE ARE THE WEB article about "The Machine" - the machine within which we already live. It is a long article, so if you are busy scroll down until the sub-paragraph 2015. That vision combined with the facts told by The Brain in The Vat-team at UCSD Neuro-science here is clearly worth of a longer story. I'll try to write that before tomorrow. Stay tuned!

Monday, April 17, 2006

Brain, Memories, Intelligence (and Google)

Jurvetson wrote in his blog "“The brain does not ‘compute’ the answers to problems; it retrieves the answers from memory… The entire cortex is a memory system. It isn’t a computer at all"
Jurvetson quotes Jeff Hawkins. Hawkins argues that the cortex stores a temporal sequence of patterns and recalls them auto-associatively. This framework explains the broad synaptic connectivity and nested feedback loops seen in the cortex and referred to in my earlier posts on synaesthesia and Jimi Hendrix chord, for example.

This is a memory-prediction (rather than "computation-centric behavior") framework for intelligence. The 30 billion neurons in the neocortex provide memories. These memory-based models continuously make low-level predictions in parallel across all of our senses.

While reading Jurvetson, I hear an other voice explaning this same "dangerous idea". This voice belongs to V.S. Ramachandran director of the Center for Brain and Cognition and the professor of psychology and neuroscience, at the University of California, San Diego. Rama's "dangerous if true idea" was "what Francis Crick referred to as "the astonishing hypothesis"; the notion that "our conscious experience and sense of self is based entirely on the activity of a hundred billion bits of jelly — the neurons that constitute the brain.

Now, says Jurvetson using the voice of Jeff Hawkins, what this jelly does, is associating memories.

Some people working with intelligent machines, once and while, refer to Alain Turing who in 1950's introduced the Turing test as a way of operationalizing a test of intelligent behavior and recognizing intelligent machines. Many of the ICT-professionals still believe and like to think that computing is, first of all logic, and it really is the LOGIC, that these intelligent humans with their intelligent machines are bringing in when they enhance the business processes with computers.

Therefore it is interesting to read what Jurvetson writes after his visit to Jeff Hawkins. Did you know that "we are entering an era for complex chips where almost all transistors manufactured are memory, not logic", or, "in the next six years, 90% of all logic chip area will actually be memory".
Read your self!

I can see a new internet business arising with companies like Google and Amazon (Mechanical Turk) leading. In this internet business you sell memories and associations based on these.

Friday, April 14, 2006

It takes so long, my Lord

My sweet lord by Billy Preston

Here Comes the Sun

Music. What is it? I keep wondering.
This is Ursula Le Guin, Always Coming Home:

“When I hit the drum like this
I think the sound
was there from the beginning,
and everything has gone to make that sound,

I could change the word drum with chord but the idea remains the same.

It's simple (the hidden order that keeps the sounds we hear together), it speaks to all of us (somehow in our brain)

I see the ice is slowly melting
It’s been a long cold lonely winter
It seems like years since it’s been here

Here comes the sun (du dn du du)
C A7
Here comes the sun
And I say
It’s alright

Little darling
C D7
It’s been a long cold lonely winter
Little darling
It seems like years since it’s been here

Ths is JJK in YouTube. He shows how melting ice is done! Watch his fingers and see the simple order.

Patsy Cline Crazy live on the Grand Ole Opry in 1962

One of the best ever, Patsy Cline singing

Patsy Cline Crazy live on the Grand Ole Opry in 1962

Crazy, I'm crazy for feeling so lonely Dm(#7) Dm7
I'm crazy, crazy for feeling so blue C#dim7 Dm7 G7

lyrics and chords here