Why We Should Build a Supercomputer Replica of the Human Brain

An anonymous reader sends this excerpt from Wired: "[Henry] Markram was proposing a project that has bedeviled AI researchers for decades, that most had presumed was impossible. He wanted to build a working mind from the ground up. ... The self-assured scientist claims that the only thing preventing scientists from understanding the human brain in its entirety — from the molecular level all the way to the mystery of consciousness — is a lack of ambition. If only neuroscience would follow his lead, he insists, his Human Brain Project could simulate the functions of all 86 billion neurons in the human brain, and the 100 trillion connections that link them. And once that's done, once you've built a plug-and-play brain, anything is possible. You could take it apart to figure out the causes of brain diseases. You could rig it to robotics and develop a whole new range of intelligent technologies. You could strap on a pair of virtual reality glasses and experience a brain other than your own."

Comments

One teensy detail

[maugle]

Simulating how the neurons and connections function won't be enough. You also need an initial state for each of them. Get even a tiny precentage of them wrong, and the result would probably be a virtual seizure.

Re:One teensy detail

[X0563511]

Let "neurons" power themselves up, simulating mitosis. Your neurons didn't just appear one day, they grew from a single gamete.

Lack of Ambition and...

[Okian Warrior]

... The self-assured scientist claims that the only thing preventing scientists from understanding the human brain in its entirety — from the molecular level all the way to the mystery of consciousness — is a lack of ambition.

This.

Also, the lack of any sort of a roadmap as to how to do this.

Also, the lack of any sort of definition for "consciousness", or any indication that it is an emergent property, or any way to measure when you've succeeded in making consciousness, or any theoretical evidence at all that it would arise from any specific plan.

We could model as many neurons as we like and it *still* wouldn't be a human brain unless we figure out how those neurons connect with each other. With no detailed plan, it's like trying to build a house by tacking boards together.

The "self-assured scientist" could start by telling us how a Cortical Column is wired up, how the feedback and feed-forward between columns works, and why artificial neural nets have inputs on one side and outputs on the other, when the brain apparently has both inputs and outputs on one side (in the sense of a functional diagram; ie - the efferent and afferent neurons connect to the same level of layer), and what the distinction is between these models.

If he can't solve basic issues, how can he hope to succeed in such a complex and ambitions project?

Re:To put it in perspective

[xtal]

Of course it's possible. It exists in your head right now.

There is even a known process by which they are constructed in ~9 months.

Non-human rights?

[Immerman]

Indeed, this seems to be something these sorts of projects forever overlook - the point. If you create a conscious model of the human brain, then you have all the same ethical problems experimenting on it as you would on an actual human, all you've done is drastically increase the potential benefits of doing so, and I for one do not particularly want to live in a world where it's accepted that you can experiment on someone's brain just because "the benefits are worth it".

You could possibly learn something new by just being able to watch it in action in excrutiating detail, but all the parts at least are only going to work in the manner you programmed them to, so really it comes down to a test case to see if our understanding of the component mechnisms of the brain has captured the "secret sauce" of consciousness. Even that though has major ethical considerations - it's unlikely to work right the first time, and all the intermediate attempts are rather analogous to intentionally creating children with severe brain damage.

And that's not to mention the fact that we may well need completely new technology to simulate a brain effectively - all existing computers are clocked, and any simulation is going to by necessity work in discrete time slices, which is completely unlike the totally asynchronous, continuous operation of an organic brain. Even if we can somehow manage the simulation by, for example, using extremely fine time slices and running it at a tiny fraction of real-time, it will still likely require several orders of magnitude more processing power than the human brain itself possesses. I mean the architectual differences mean it took a decent Pentium-class machine in order to be able to simulate an ancient AtariXT in real time, and those two systems are practically identical compared to a brain.

Re:Non-human rights?

[Immerman]

The point though, for clocked versus non-clocked processing, is that there is potentially a great deal of information encoded into the specific timing of a pulse and how it interacts with the specific timing of the hundreds or thousands of other pulses being received by each of the target neurons. A given neuron may only be able to fire say a hundred times per second (I don't know offhand), but that in no way implies that its information processing capacity is anywhere near as limited a similarly interconnected 100Hz microprocessor (yes, processor - recent discoveries have shown that individual neurons don't operate as threshold-triggered transistor-analogs as once believed, but instead exhibit non-trivial memory and signal processing behaviors)