Probably not in 5 years. But even if, it would only be a step. A big and worthwhile step, mind you, but look at the C. elegans and stomatogastric people: they've had their connectomes for quite some time now (1990s) and still don't fully understand how it all works.

Posted by: Björn Brembs | August 11, 2009 10:37 AM

My friend just got a job in Germany trying to get this working for mice with this guy. I'd imagine that will be done in 5 years. Humans would probably be another 5 or 10 years after that, although it might take a ridiculous amount of storage, as my friend was already mentioning dealing with petabytes of data for mice.

Posted by: Kevin H | August 11, 2009 2:14 PM

In the article, you write:

"Neurons can sprout new connections within minutes of a given stimulus..."

I found that interesting. I was under the impression that stimulus dependent plasticity is mainly the strengthening and weakening of synaptic connections as in Hebbian learning rules, since, afaik, we start of with more synapses than we need and gain function through the pruning of the ones not needed and the tuning of synaptic strength.

If neurons, throughout life, sprout new connections in response to stimuli, what guides the axons so as to facilitate optimal response to the kind of stimuli presented. I was under the impression that axonal guidance worked primarily through chemotaxis along glial structures in development. I guess my main questions is: How would new axons wire to increase functionality in light of the above?

On a side note - I completely agree with the points you make: Plasticity and glial contributions seem essential to understanding brain-function, and I can't see how we should have the technology to make a sufficiently detailed human connectome.

Also, I wonder what you make of these publications on connectomes:

* Hagmann P, Kurant M, Gigandet X, Thiran P, Wedeen VJ, Meuli R, Thiran JP (2007) Mapping human whole-brain structural networks with diffusion MRI. PLoS ONE 2, e597.

* Hagmann P, Cammoun L, Gigandet X, Meuli R, Honey CJ, Wedeen VJ, Sporns O (2008) Mapping the structural core of human cerebral cortex. PLoS Biology 6, e159.

* Izhikevich, EM, Edelman, GM (2008) Large-scale model of mammalian thalamocortical systems. PNAS 105, 3593-3598.

Posted by: MPhil | August 11, 2009 3:51 PM

#4
the arguably most profound topic of neuroscience, consciousness, has not much to do with plasticity and everything to do with the connections in a brain. The secret to consciousness will be in that wiring diagram

How could you possibly know that?

#7
Consciousness is far more complicated than the sum of connections in the brain, more like a continuous sequence of transient whole-brain connectivity configurations, each lasting just thousandths of a seconds.

Or even that?

(Without knowing what consciousness is first, which, of course, we don't.)

Posted by: Nigel | August 12, 2009 2:48 AM

Mo: regardless of what you "think" consciousness is what you lack for your assumptions is any definitive proof to support your bold claims. If consciousness were so easily explained as simply (which of course is nowhere near simple) transient connectivity configurations then permit me to ask a question or two.

1. If it does turn out to be transient connectivity configurations, which of those account for what is "essentially" consciousness? Can simple bio-electrical currents and neuro connectivity truthfully and honestly be shown as a picture or even interactive map shown in real time, and pointed at and said about with any real certainty "This is what human consciousness is"?

2. Is human consciousness reducible to any single set of connectivity configurations? Because saying that it is more than one set of connectivity configurations makes one wonder just exactly which of the many numerous configurations actually have to do with consciousness and which are simply reflexes, if it IS in fact a single set of them, then, you're looking at a set of connectivity functions that is impossibly complex and could never be mapped or discovered.

I think this article is an ambitious goal, but will ultimately be of limited use pertaining to actual consciousness. Even if the claim was made about it that "this represents the human consciousness" then there will always be skeptics like Nigel above who will always be able to ask "How could you possibly know that?" and they will be right for asking. Furthermore, there is no answer anyone could give that will satisfy the question. You couldn't know that. No matter how much "scientific" proof you give, consciousness will likely fall into those cracks between certainty and questioning. It very well MIGHT be as you say. But even if it IS as you say, you could never know with any real certainty if it was or not.

Posted by: Nathan | August 12, 2009 3:11 PM

Mo:

"But it would certainly involve this, at the very least, because the activity patterns associated with that sequence of configurations are the neural correlates of consciousness."

This is an unprovable statement and so I find it hard to be as certain as you are about it. While I also agree that it is likely true, at least to a certain extent, there really isn't a way to dive into a persons "private subjectivity" to understand how their consciousness is reacting or interpreting or understanding, or feeling, or....ect. So even if it plays a role, what role, and how that role is even related to consciousness? I shall quote an intelligent source to respond to these questions.

"I doubt we'll ever fully understand how consciousness emerges." -Mo

In other words, I agree...and disagree at the same time, but not with your principle, more with your certainty about the principle.

Posted by: Nathan | August 12, 2009 4:12 PM

"We can make reliable inferences about such things, just as we make inferences about what goes on inside of stars, or what happened microseconds after the Big Bang, or who killed Lincoln even though none of us were there."

And to me this is utterly incoherent. What is a "reliable" inference? I am assuming (another inference) that you are referring to empirical evidence based on scientific discovery that has been repeated at least "enough" times to actually cause us to live under the belief that "such and such" occurs.

Tell me what evidence we have that consciousness even exists at all, or that we each individually have a different one? People have made similar inferences based on Newtonian physics, which turned out to not be exactly right...and phlogiston theory which we NOW know to be utter nonsense but when it was popular was considered to be undeniable truth. People thought the earth was flat for hundreds of years and inferred things from that. What you are claiming is that those inferences were and are just as accurate and compelling and true as any other inference made from science throughout the history of science. That is quite simply nonsensical.

So much like phlogiston, you claim that me being careful what I say about subjective experience is utter nonsense but I say that, you can say whatever you want to about my statements, but here's the proof I submit to you that you could not make a correct inference about my subjective experience. Based on the paragraphs above, I believe that from my own subjective experience, a person who thinks that a man like Dennett has the whole of consciousness somehow explained or accounted for must then therefore mean that you are paying me a...compliment...by saying that I speak incoherent nonsense because what I say doesn't line up with what you tend to want to infer about the world.

Now the explanation here is that I (once again) infer from your tone above that you were actually trying to say that what I had previously said deserved to be slashed to bits and was so worthless it was worth only the attention given in order to bash it and send it away crying, but in fact, I take it as a compliment based on other inferences. So which of us made the correct inference? Which, if any of them, are "reliable" and who decides that they are reliable? Is there an expert who we defer to on such things? Because I have to tell you, that appears like buying into a paradigm for the sake of the paradigm and vigorously defending it as though it were a priori truth, when in fact there is plenty of past evidence to suggest that paradigms, while perfectly useful, certainly tend to not be quite right. (Theory of gravity, Newtonian Physics, Phlogiston, The earth is flat, The sun revolves around the earth ect.) Giving no credit to coherent statements such as mine above is no better than simply saying you do not understand it and so you will pay it no mind.

Posted by: Nathan | August 13, 2009 8:36 AM

Thank you for the article, Mo. Really interesting project. Even a rough map of connection may help scientists unraveling the mechanisms behind neurological and psychiatric diseases, so why aim at consciousness right away..

Posted by: CopperKettle | August 17, 2009 7:36 AM

Hardy Falk,
I'm not surprised on how slow are we going. I'm surprised on how fast the understanding of the brain is going considering the extreme dificult of the subject.
The big advantage of the Blue Brain Project is the integration of such different knowledge.
We have a lot of research in molecular bases of neuroscience, but not as much in the concections arena. So this conectoma development is a wellcome and needed effort.

Posted by: Antonio Orbe | August 31, 2009 7:20 AM