Understanding the Brain

Artificial brain

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Artificial brain is a term commonly used in the media[1] to describe research that aims to develop software and hardware with cognitive abilities similar to the animal or human brain. Research investigating "artificial brains" plays three important roles in science:

  1. An ongoing attempt by neuroscientists to understand how the human brain works, known as cognitive neuroscience.
  2. A thought experiment in the philosophy of artificial intelligence, demonstrating that it is possible, in theory, to create a machine that has all the capabilities of a human being.
  3. A serious long term project to create machines capable of general intelligent action or Artificial General Intelligence. This idea has been popularised by Ray Kurzweil[2] as strong AI (taken to mean a machine as intelligent as a human being).

An example of the first objective is the project reported by Aston University in Birmingham, England[3] where researchers are using biological cells to create "neurospheres" (small clusters of neurons) in order to develop new treatments for diseases including Alzheimer's, Motor Neurone and Parkinson's Disease.

The second objective is a reply to arguments such as John Searle's Chinese room argument, Hubert Dreyfus' critique of AI or Roger Penrose's argument in The Emperor's New Mind. These critics argued that there are aspects of human consciousness or expertise that can not be simulated by machines. One reply to their arguments is that the biological processes inside the brain can be simulated to any degree of accuracy. This reply was made as early as 1950, by Alan Turing in his classic paper "Computing Machinery and Intelligence".[4]

The third objective is generally called artificial general intelligence by researchers.[5] However Kurzweil prefers the more memorable term Strong AI. In his book The Singularity is Near he focuses on whole brain emulation using conventional computing machines as an approach to implementing artificial brains, and claims (on grounds of computer power continuing an exponential growth trend) that this could be done by 2025. Henry Markram, director of the Blue Brain project (which is attempting brain emulation), made a similar claim (2020) at the Oxford TED conference in 2009.[1]

Approaches to brain simulation

Although direct brain emulation using artificial neural networks on a high-performance computing engine is a common approach,[6] there are other approaches. An alternative artificial brain implementation could be based on Holographic Neural Technology (HNeT) non linear phase coherence/decoherence principles. The analogy has been made to quantum processes through the core synaptic algorithm which has strong similarities to the QM wave equation.

EvBrain[7] is a form of evolutionary software that can evolve "brainlike" neural networks, such as the network immediately behind the retina.

Since November 2008, IBM received a $4.9 million grant from the Pentagon for research into creating intelligent computers. The Blue Brain project is being conducted with the assistance of IBM in Lausanne.[8] The project is based on the premise that it is possible to artificially link the neurons "in the computer" by placing thirty million synapses in their proper three-dimensional position.

In March 2008, Blue Brain project was progressing faster than expected: "Consciousness is just a massive amount of information being exchanged by trillions of brain cells.[9]" Some proponents of strong AI speculate that computers in connection with Blue Brain and Soul Catcher may exceed human intellectual capacity by around 2015, and that it is likely that we will be able to download the human brain at some time around 2050.[10]

There are good reasons to believe that, regardless of implementation strategy, the predictions of realising artificial brains in the near future are optimistic. In particular brains (including the human brain) and cognition are not currently well understood, and the scale of computation required is unknown. In addition there seem to be power constraints. The brain consumes about 20W of power whereas supercomputers may use as much as 1MW or an order of 100,000 more (note: Landauer limit is 3.5x1020 op/sec/watt at room temperature).

Artificial brain thought experiment

Some critics of brain simulation [11] believe that it is simpler to create general intelligent action directly without imitating nature. Some commentators[12] have used the analogy that early attempts to construct flying machines modeled them after birds, but that modern aircraft do not look like birds. A computational argument is used in AI - What is this, where it is shown that, if we have a formal definition of general AI, the corresponding program can be found by enumerating all possible programs and then testing each of them to see whether it matches the definition. No appropriate definition currently exists.

In addition, there are ethical issues that should be resolved. The construction and sustenance of an artificial brain raises moral questions, namely regarding personhood, freedom, and death. Does a "brain in a box" constitute a person? What rights would such an entity have, under law or otherwise? Once activated, would human beings have the obligation to continue its operation? Would the shutdown of an artificial brain constitute death, sleep, unconsciousness, or some other state for which no human description exists? After all, an artificial brain is not subject to post-mortem cellular decay (and associated loss of function) as human brains are, so an artificial brain could, theoretically, resume functionality exactly as it was before it was shut down.

See also

References

  1. 1.0 1.1 Artificial brain '10 years away' 2009 BBC news
  2. Kurzweil, Ray (2005), The Singularity is Near, Viking Press 
  3. Aston University's news report about the project
  4. The critics: Turing's (pre-emptive) response: Other sources that agree with Turing:
  5. Voss, Peter (2006), Goertzel, Ben; Pennachin, Cassio, eds., Essentials of general intelligence Artificial General Intelligence, Springer, ISBN 3-540-23733-X, http://www.adaptiveai.com/research/index.htm#different_approach Essentials of general intelligence 
  6. see Artificial Intelligence System, CAM brain machine and cat brain for examples
  7. Jung, Sung Young, "A Topographical Development Method of Neural Networks for Artificial Brain Evolution", Artificial Life, The MIT Press, vol. 11, issue 3 - summer, 2005, pp. 293-316
  8. Blue Brain in BBC News
  9. (Template:ISO 639 name en) Out of the blue
  10. (Template:ISO 639 name en) Jaap Bloem, Menno van Doorn, Sander Duivestein, Me the media: rise of the conversation society, VINT research Institute of Sogeti, 2009, p.273.
  11. Goertzel, Ben (Dec 2007). "Human-level artificial general intelligence and the possibility of a technological singularity: a reaction to Ray Kurzweil's The Singularity Is Near, and McDermott's critique of Kurzweil". Artificial Intelligence 171 (18, Special Review Issue): 1161–1173. doi:10.1016/j.artint.2007.10.011. http://scholar.google.com/scholar?hl=sv&lr=&cluster=15189798216526465792. Retrieved 1 April 2009. 
  12. Fox and Hayes quoted in Nilsson, Nils (1998), Artificial Intelligence: A New Synthesis, p581 Morgan Kaufmann Publishers, ISBN 978-1-55860-467-4

External links