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The Singularity and the Neural Code

I wish I could believe that we are rapidly approaching “The Singularity.” Like heaven, the Singularity comes in many versions, but most involve bionic brain boosting. At first, we’ll become cyborgs, as brain chips soup up our perception, memory, and intelligence and eliminate the need for annoying TV remotes. Eventually, we will abandon our flesh-and-blood selves entirely and upload our digitized psyches into computers.

Singularity enthusiasts, or Singularitarians, tend to be computer specialists, such as entrepreneur Ray Kurzweil. Citing the explosive progress of information technologies captured by Moore’s Law, Kurzweil prophesies a “merger of biological and nonbiological intelligence” that will culminate in “immortal software-based humans.” The Singularity will supposedly happen within decades.

Specialists in real rather than artificial brains find these predictions laughably naïve, because we are still so far from understanding how brains make minds. “No one has the foggiest notion,” says Nobel laureate Eric Kandel. “At the moment all you can get are informed, intelligent opinions.”

Singularitarians nonetheless insist that brains are just complicated computers, and there is some basis for this analogy. Neurons resemble transistors, absorbing, processing, and reemitting the electrochemical pulses known as action potentials. Also called spikes, a reference to their appearance on oscilloscopes, action potentials serve, supposedly, as the brain’s basic units of information.

Barring our admittance to cyber-paradise, however, is the neural code. That phrase refers to the software, or algorithms, that transform action potentials and other physiological processes into perceptions, memories, meanings, intentions.

The neural code is science’s deepest, most consequential problem, but it is also by far the hardest. The prominent neuroscientist Christof Koch doubts that the neural code “will be anything as simple and as universal as the genetic code.” He adds that there may be “no universal principle” governing neural-information processing beyond the insight that “brains are amazingly adaptive and can extract every bit of information possible, inventing new codes as necessary.” So little is known about how the brain processes information that “it’s difficult to rule out any coding scheme at this time.”

British neurobiologist Steven Rose points out that each individual’s brain is unique and ever-changing. To dramatize this point, Rose poses a thought experiment involving a “cerebroscope,” which can record everything that happens in a brain, at micro and macro levels, in real time.

Let’s say the cerebroscope records all of Rose’s neural activity as he watches a red bus coming down a street. Could the cerebroscope reconstruct what Rose is feeling? No, because his neural response to even that simple stimulus grows out of his brain’s entire previous history, including a childhood incident when a bus almost ran him over.

To interpret the neural activity corresponding to any moment, Rose elaborates, scientists would need “access to my entire neural and hormonal life history” as well as to all his corresponding experiences. Scientists would also need detailed knowledge of the changing social context within which Rose has lived; his attitude toward buses would be different if terrorists had recently attacked a bus.

This analysis implies that each individual psyche is fundamentally irreducible, unpredictable, inexplicable. It is certainly not simple enough to be extracted from a brain and transferred to another medium, as Singularitarians assume.

Let’s face it: The Singularity is a religious rather than a scientific vision. The yearning for transcendence, whether spiritual or technological, is all too understandable. Both as individuals and as a species, we face deadly serious problems, from terrorism to climate change. Engineers and scientists should be helping us face the world’s problems and find solutions to them, rather than indulging in escapist, pseudoscientific fantasies like the Singularity.

John Horgan directs the Center for Science Writings, which belongs to the College of Arts & Letters. This column is adapted from one originally published on his ScientificAmerican.com blog, “Cross-check.”