The Internet and the Brain
by Chris Woodford. Last updated: January 28, 2018.
Brains are like computers, computers are like brains—you'll often hear people comparing the most advanced bit of kit nature has produced with the best that mankind has managed (so far). Sometimes the comparison gets personal and competitive. When Gary Kasparov was pitched against IBM's Deep Blue computer in a series of nail-biting 1997 chess matches, there was more at stake than the computer maker's reputation or the Russian's prickly pride: many people started asking whether electronic brains could finally be considered as intelligent as human ones. Since Kasparov lost to the big blue supercomputer, the Internet has moved center-stage in many of our lives—and a lot of people are now asking a subtly different question: if lots of people are hooked up to one another by a giant worldwide computer network, do they work together in a brain-like way? In short, is the Internet becoming a kind of worldwide brain? Well... let's take a closer look and find out!
Photo: Interbrain: we know the brain can be fruitfully compared to a computer, and vice-versa, but what can we learn by comparing the brain with the Internet and the World Wide Web? Brain photo courtesy of National Institute on Drug Abuse and National Institutes of Health (NIH) with overlaid neural network by explainthatstuff.com.
Why compare Net and brain?
Is there any value in comparing two things as unlike as the Internet and the human brain? Many people have tried. One of the first was French philosopher-priest Pierre Teilhard de Chardin (1881–1955); a radical and controversial thinker, he anticipated the Web over 50 years ago when he imagined a new stage of human evolution with people linked together to form a kind of collective, densely interconnected mind, heading for a union with the divine . A more recent attempt, by Peter Russell, dates back to 1995, when the Internet was fully realized but most people had still not heard of (much less used) the World Wide Web. In his book The Global Brain Awakens: Our Next Evolutionary Leap, Russell suggested that a fizzing global network of densely interconnected humans would form the springboard for the next stage in human development , although artificial intelligence researcher Mark Humphrys dismisses such simple comparisons of Net/Web and brain as "vague and unconvincing analogies." 
Describing the Internet as a brain is indeed an analogy or metaphor, but is it merely a metaphor? It's worth remembering that two of the great movements in 20th century psychology were similarly inspired by metaphors. Behaviorism suggested the mind was a kind of "black-box" with inputs (stimuli of various kinds) producing outputs (matching responses) through internal processes that might or might not exist but, either way, were beyond study through previously dependable methods such as introspection. There were "no user-serviceable parts inside"; all that could be studied were observable external events. Cognitive psychology, an aversive reaction to behaviorism that displaced it as the dominant metaphor from the early 1960s, suggested the brain was a computer-like information processor made from discrete, modular components that operated (or failed) in isolation—and could certainly be studied that way too. In the eager hands of cognitive psychologists, the mind's tight and rusty screws were prised open and internal mental processes once again laid bare. Both metaphors proved to be heuristics—powerful but recognizably imperfect working models—that moved psychology, still a relatively young science, much further forward.
Questioning questions is important. Instead of asking "Is the Internet like a brain?" or even "Does it helps to compare the Internet and the brain?", maybe the best approach is to say "What heuristic value lies in the comparison? Does it help us to discover more about the brain or the Internet and to move brain science and Internet technology forward?" Those are the questions I'll be considering here.
First off, what can we learn by comparing the way brains and computer networks are made?
Artwork: If you were to cut vertically through the middle of your head, from top to bottom, through a line that passes through the center of your nose, you'd see a cross-section of the brain's main functional areas like this. Image courtesy of National Institute on Alcohol Abuse and Alcoholism (NIAAA).
Most of us have a basic grasp of brain anatomy. We know the human brain is made of two hemispheres (sides) connected by a kind of "parallel cable" called the corpus callosum. Each hemisphere is divided into four regions called lobes, which neuroscientists suggest play differing roles in different kinds of behavior. So, for example, it's known that the temporal (side) lobe plays an important part in memory, the frontal lobe is involved with planning our actions, and the parietal and occipital lobes (at the middle and back of the brain) are where we process information from our eyes and other senses. It's (at best) an oversimplification to suggest that the different functions of the brain are localized in certain precise brain regions (as the phrenologists famously tried to do) and equally misleading to claim that the two hemispheres are like a dysfunctional married couple trapped in a small house ("the right brain is more creative; the left brain is more logical"). For the purposes of our present comparison between the brain and Internet, what's of most interest is the way the cerebral cortex of the brain (the convoluted top part where all the interesting, human stuff happens) is made from billions of neurons (brain cells) that "wire together, fire together"  in elaborate patterns, enabling everything from simple pattern recognition to long-term memory.
When we talk about the Internet, it's important to be clear that we really mean the Internet (the global network of interconnected computers) and not the World Wide Web (the multimedia library of text, graphics, videos, and other stuff that we access over the Net, for example, when we Google or use Wikipedia). The Web is only one of many applications that use the Internet, including email, VoIP (Internet telephony, such as Skype), IPTV (television), and P2P file-sharing applications. There's actually a value in comparing the brain to both the Internet and the World Wide Web, but it's important to distinguish between the two and be clear. The Internet is hundreds of millions of computers (including computing devices such as cellphones and all kinds of automated machines that communicate over the Net). The Web is hundreds of millions of websites, most of which contain links (once known as hypertext links—though that's now starting to sound impossibly old-fashioned) to other pages on the same site and other websites entirely.
If you send an email or browse a webpage, packets of data travel over something like six to ten links between your computer (a browser or client) and the distant computer you're communicating with at the other end (a server) . That gives you some idea of how many "layers" of networks are involved in linking any two points on the Internet; there isn't simply a one-to-one connection (at least, not in most cases).
It's easy to make crude anatomical comparisons between the brain (on one hand) and the Web and the Net (on the other). Where the brain has cells firing across synapses, the Net links computers over ethernet cables, fiber-optic cables, or satellite links, and the Web uses hypertext links to connect one page to others. Now all computers on the Net are not equally important. There are major links between continents, for example, carried in a relatively small number of hugely important undersea cables ; if one of those fails, vast amounts of Internet traffic are slowed down as they reroute across the world via longer and less direct routes . In the same way, some web pages are more important (and authoritative) than others. Google built its success on using an algorithm called PageRank to rate more highly pages that were more densely interlinked, supposing that they were more important than less-linked pages . So its own homepage, Google.com scores highest with a PageRank of 10, while an average, good quality page might score 3–4. The sudden loss of Google would (initially) be a major blow to the Web, though we'd quickly find alternatives; the loss of a PageRank 3–4 site or page wouldn't bother us at all.
Does the brain operate the same way? It's certainly true that aspects of our behavior are controlled by circuits of activity within the brain. So, for example, neuroscientist Joseph Le Doux has devoted much of his career to fathoming out the complex circuits involved in emotions such as fear . Cognitive psychologist Alan Baddeley has advanced a successful theory that our "working memories" (short-term memories where we process immediate sensory impressions and things we're thinking about) are made up of various discrete components (such as storage areas for recording impressions from our eyes and ears), also linked in essentially sequential circuits, though it remains uncertain exactly how they map to particular regions within the brain .
Cognitive neuropsychology is the fruitful field that marries cognitive psychology (the computational theory of the mind) with the actual anatomy of the brain, and it uses two main approaches. One is to observe patients with particular patterns of brain damage (often small-scale lesions damaging relatively specific brain areas) to see what kind of cognitive problems they have, and then use those to refine cognitive theories such as memory, perception, and attention. The other is to look at a cognitive model of something like memory or perception, speculate what might happen if part of it becomes damaged, and try to find a real-world patient with exactly those symptoms.
Summing up, what do we see from a crude anatomical comparison? The brain is modular, with some degree of specialization between different regions, and works in parallel. The Web and the Net are similar: you can damage relatively large parts of either without affecting the operation of the whole thing—and (Web or Net) it's likely that it will rapidly recover from damage by relocating the things it used to do in the damaged areas to other, intact places. Our brains have the same kind of plasticity, especially when they're young (somewhat less so when we're older).
Send an email to a friend and it's very different from mailing them a letter. While you're letter travels in one piece along one particular (though not necessarily predictable) route, your email will be broken up into many separate packets, each with its target address attached, and each traveling over whatever route seems best at the time. Packet switching, as this is known, has proved to be a hugely efficient way to send huge amounts of data around the world. One of its main advantages is that it can usually (but not always) route traffic around damage or congestion on the Net.
Picture: Moving house by packet switching: you'd dismantle your home and mail the bricks separately. After they traveled in parallel by (potentially) separate routes, you'd reassemble them once they reached their destination. Read more in our article on how the Internet works.
MIT's Daniel Graham and Daniel Rockmore have recently suggested that it's profitable to consider whether the brain (specifically the cortex) communicates in similar ways. At the very least, they argue, that shifts the focus away from the computational emphasis of cognitive psychology (what happens inside the flowchart boxes of the mind) to greater consideration of how different parts of the brain actually communicate (how the boxes link together). More radically, they suggest there might be something to be gained by exploring whether the brain shuffles information in a similar way to how the Net switches packets between discrete domains. Wisely, though, they end their comparison with a caution: "As grand descriptions, analogies to technology all ultimately fail to account for major aspects of brains. No single mechanistic description has achieved more than a rudimentary description of perceptual or cognitive systems."  (But if they're heuristics, of course, that doesn't matter.)
The brain and the Net are essentially linear. You can't send an email from London, England to someone in Tokyo without it traveling through various intermediate domains (though it's important to remember that Net traffic doesn't flow as the crow flies, much less how the boat sails or even how the telephone call is routed). In the same way, if you see something, information has to pass in a certain sequence from the retinas in your eyes to the visual cortex in your brain (in the occipital lobe of whichever eye is seeing at the time). The same is not true of the Web. Any Web page can link to any other without passing through any intermediate page or pages, though there is usually some meaningful connection: links are (generally) not random. This spontaneous connectivity is one of the things that's made Twitter so popular and successful. With a single click of your mouse, you can immediately "follow" your favorite celebrity—Stephen Fry, Ashton Kutcher, or whoever—and be one of thousands tweeting them at any given moment. And nothing much changes in the world. But if your tweet catches their attention and they tweet you in return, follow you, or ask their followers to follow you, you can find yourself suddenly followed by hundreds or thousands of people who never previously knew of your existence. Through one or two simple "links" (the tweet you sent and the one you received in return), the Web has slightly but significantly rewired itself. A direct new link has been made from one side of cyberspace (Stephen Fry) to the other (you) without passing through anything or anyone in between. The spontaneous creation of links between previously unrelated parts of the Web is one of the most creative and exciting possibilities of cyberspace—and one that remains largely unexplored.
It's easy to get carried away with fanciful comparisons between brain, Web, and Net—unless you remember that they're designed to do completely different jobs. Although we might have high-flying notions about philosophy and poetry, the blunt truth is that our brains are designed to run our bodies, nothing more and nothing less. That's why behaviorism proved to be relatively successful: we can understand a certain amount of human behavior as mere "animal behavior," at its crudest, almost knee-jerk reflexes from sensory stimuli to motor (muscular) responses. The Internet and the Web obviously have no body to control: the Internet's purpose is to carry information from one computer to another, while the Web is a highly dynamic repository of human knowledge. Push behaviorism aside, and start to ask how exactly the brain controls the body, and it's immediately clear that brains have internal functions that resemble those of both the Net and the Web: they carry information (like the Net) and they're active repositories of knowledge (like the Web). Now it's easy to see obvious parallels between, say, human memory and computer memory; but, instead, let's explore the comparison further by considering something less obvious, perception and pattern recognition, which is one of the human brain's most important functions.
Processing sensory information—seeing, hearing, smelling, tasting, or touching something—is largely about recognizing patterns, which is why it's fair to say that much of what we see happens in the brain rather than the eye. From recognizing faces to reading written language, visual perception is substantially a problem of pattern recognition. From the mid 1980s or so, psychologists and computer scientists joined forces to develop neural networks, which are computer models of pattern recognition based on layers of connected "units" roughly analogous to brain cells. You can train a neural network to recognize things by presenting it with many different examples. So if you show it a hundred pictures of dogs and a hundred pictures of cats, and explain which is which, it should be able to tell you whether a picture of an unknown animal is either a cat or a dog. Neural networks are built from layers of discrete units connected together by links of different "weight" and they learn links by a feedback process (typically one called back-propagation) that adjusts the weights of the links each time new information passes through them.
Photo: A neural network recognizes patterns using interconnected layers of input units (red), hidden units (blue), and output units (yellow). The weights of the connections between the units represent, in distributed form, the things the network learns.
Can the Net or the Web recognize patterns in similar ways to the brain, using something like a neural network? It's hard to see any comparison with the Net. The domains between which packets of information are switched are not linked by connections whose weight changes. The Net doesn't change the way it carries information according to the meaning of the information it carries. Indeed, the whole reason the Net has been such a successful design is that it takes no account whatsoever of the type of information it carries. That means a network that was originally conceived to carry simple messages between computers (such as emails) has also been able to carry Web pages, VoIP telephone calls, TV pictures, and much more besides. (Technically, this is known as the end-to-end principle, which means that the inner structure of the network hasn't been designed according to what the network itself is carrying, and it's related to the similar concept of Net neutrality, where all Internet traffic is treated the same way.)
But what about the Web? Does that function as a neural network? Does it recognize patterns? It's certainly true that the Web consists of discrete points (websites) connected to other discrete points (other domains) by weighted links. Although, in principle, every link on the Web is the same as every other link, some links clearly carry more weight than others: as we've already seen, that's why Google gives much more credit to a link to your website from NASA, the BBC, or the White House than from Acme Dishwashers or Billy's Elvis Presley Fan Site. So the Web has some of the structure of a neural network, but can it function the same way? There's a key difference between a neural network and the Web that we've not yet considered. While all the "units" in the Web (websites) are, in principle, equivalent, the units in a neural network fall into three different types: input units (through which new information is fed in), output units (where results appear), and hidden units (in between the input and output units where the actual processing is done). In the diagram up above, information flows through the network as it does in a computer, from input through processing (hidden units) to output (as drawn, from left to right). The Web corresponds to the hidden units in the middle of a neural network: it has no obvious input or output. Not only that, but it's not arranged to process information in a linear fashion, like a neural network. It's more like a sphere built entirely from hidden units, where any hidden unit can, in theory, connect with any other (and not just the units either side, as in a simple neural network).
But can we stretch the analogy just a little more? We might consider whether certain units of the Web can act as inputs and outputs. Blogs, for example, often pick up exciting topical developments from the real world, which are then discussed and disseminated by other blogs and other websites before, occasionally, prompting dramatic real-world events of their own. Back in 2002, for example, in what is often cited as the first big demonstration of blog power, US politician Trent Lott famously resigned as Senate Republican Leader after bloggers seized on a careless remark he made that they considered racist, but which the mainstream media had chosen to ignore. After much heated online debate, the now-amplified story was eventually picked up again by mainstream journalists and so much attention was focused on Lott that he decided to stand down . Was this an example of the Web acting like a neural network? Attentive websites had served as the inputs, the interlinked network of blogs, websites, and social networkers discussed and disseminated those inputs, hyping them up or playing them down, and finally, the network as a whole somehow arrived at an aggregated conclusion (an output) that prompted very real action? The interesting thing about this analogy (and it is only an analogy) is that any website (or Facebook or Twitter account) might act as an "active" input or output or a more "passive" hidden unit, merely playing a small part in the collective pattern-recognition and decision-making process. So if the Web is, in any sense, a neural network, it's a very special kind of neural network where the input, hidden, and output units are in a constant state of flux.
Brains are complex and wobble about, dangerously exposed, on the tops of our heads. If they're lucky enough not to suffer physical damage through something like a head injury, they have to survive mental illness (which affects a third of us at some point of our lives ), and gradual deterioration as we get older. The field of abnormal psychology considers behavioral changes caused by psychiatric disorders such as schizophrenia and depression, while neurology and neuropsychology probe the various cognitive disorders caused by brain damage such as following a stroke. It's intriguing to consider whether the Net and the Web could suffer analogous problems.
People suffer from psychiatric disorders for a whole variety of different reasons, from "life events" (a failed marriage could plunge you into depression) to imbalances in brain chemicals (now widely supposed to cause crippling disorders such as schizophrenia). It seems to stretch the analogy too far to consider the Net or the Web developing similar problems. As we've already considered, there's more mileage in thinking about whether the Net or the Web can be degraded by localized damage—and how they might react and respond. We'd only expect the Web (say) to show a brain-like response to "lesions" if it were arranged in a modular fashion. To a certain extent, that's true: websites, for example, are specialized and dedicated to particular topics. If the most authoritative website about dogs (say a site that most dog owners relied on for all their information) disappeared overnight, we might expect the Web to experience something akin to highly selective amnesia. But it would still have perfect knowledge about cats and other animals, some knowledge of dogs would survive dispersed across other websites, and, sooner or later, someone else would reconstruct the original dog knowledge on a different website, maybe even better than the original.
Libraries are sober zones where even talking may be forbidden; emotions are cooled, calmed, dispersed, and dissipated. Individual books might be ranting polemics, but a library as a whole has no overriding opinion on any subject. Encyclopedias such as Wikipedia embody a similar spirit with a policy known as neutral point of view (NPOV): articles have to show balance without obviously favoring one argument or another. The Internet is a neutral place too: thanks to network neutrality, the traffic that travels from A to B speeds or chugs from domain to domain irrespective of whether it's the President's State of the Union address or a vile example of racist hate speech; in a democracy with a right to free speech, that's exactly what we might expect.
The Web, on the other hand, is quite different. Happy, angry, elated, or sad, websites can certainly convey an emotional tone, but it's static—and not quite the same thing as the ever-changing emotions that flood through our own brains. Blog posts can obviously be emotional too, and here the tone can fluctuate from day to day or even minute to minute. Still, although the emotions are variable, the emotions expressed in any one post are essentially frozen in time: whether it's a happy post or an angry post, that's what it will always be.
Is there any kind of analog for the fluctuating, responsive emotions in the human mind? The aggregated emotions of what's called the blogosphere and the Twittersphere  come closer. You'll often read reports saying things like "The blogosphere went wild..."; indeed, if you search for the exact phrase "the Twittersphere went", you'll get a variety of emotional options, including "crazy," "nuts," "berserk," "to war," "into overdrive," "ballistic," "supermental," "into record-breaking mode," "wild with speculation"—and so on. Does this collective chit-chat amount to anything that could be described as an emotional response? Maybe we should ask that question on Twitter?
We could argue at length over a definition of intelligence, but let's assume it's one of the things that most distinguishes humans from "less-sophisticated" animals and (flying in the face of the Turing test) machines like computers and robots . Let's say it's an ability to improvise (generalize or abstract a novel response) from previous experiences to solve some problem you've never previously encountered. The human brain is intelligent, by definition; we deem it so just by having invented the concept of intelligence. But is there any sense in which the Internet or the Web could be considered intelligent? The question has no obvious meaning where the Net (which is merely concerned with communication) is concerned. But what about the Web? What about things like the blogosphere and the Twittersphere? Do they have an intelligence beyond the intelligence of their individual users? The very existence of those terms suggests there's a meta level on which the Web now operates; that, in turn, raises the possibility of meta-phenomena such as intelligence, self-awareness, and consciousness (which may or may not be the same thing).
Is the Web self-aware? Does a blog post about the blogosphere or Twittersphere "going wild" amount to the early stirrings of self-awareness and consciousness? Isn't that taking the analogy too far? I think it probably is. One of the key aspects of consciousness is surely the sense of being the "internal conductor" of your own mental and physical orchestra (however specious that may be ): you are actively conscious of being or doing something yourself, but you can't be conscious on behalf of someone else. Thus, I can feel conscious that I am "staring out of my eyes" and typing these words now, just as you can feel conscious that you're staring out of your eyes and reading them. But I can't be conscious on your behalf that you're reading the words; and, in the same way, I can't be conscious, as a blogger, on behalf of something called the blogosphere; even if I'm an active part of it, I might just as well be a passive commentator. Blogging that "the blogosphere went wild" is entirely different from saying "I scored that goal," not least because the first statement has to be shared, externally with other people, while the second can remain valid purely as an internal thought. A conscious Web would be something entirely different. Consciousness would be quintessentially meta: something above, beyond, and entirely apart from the Web itself, something that we, as mere constituents, would presumably have no more way to experience than an individual brain cell could experience human consciousness.
Photo: Self-awareness: Is there anybody out there? It's easy to comprehend things smaller than you are, but harder to grasp that you're part of something bigger—like a galaxy of stars or even the entire universe. Would we, could we, be aware of the Internet's or Web's self-awareness, if it ever did occur? Photo of stellar swarm M80 (NGC 6093), a dense star cluster in the Milky Way galaxy, taken by the Hubble Space Telescope and courtesy of NASA on the Commons.
Is the possibility of a conscious Web good, bad, or ugly? Commentators such as Jaron Lanier have already speculated that the rise of the "hive mind" (a popular term for the kind of aggregated, anonymous actions, reactions, and emotions we see online) comes at the expense of what is most unique and beautiful about individual humans . Others are more optimistic. In an occasionally fanciful book entitled World Wide Mind, science writer Michael Chorost suggests how ingenious, technically plausible neural implants called "rigs" could be used to interconnect humans so they could directly experience one another's thoughts and emotions, heralding the possibility of a kind of Wi-Fi global consciousness leading to a "larger, more capacious, more empathetic species." 
Then again, we have to remember that this whole exercise of comparing the brain, the Web, and the Net is simply an analogy and a heuristic. So the questions we should really be asking are not "Is the Web conscious?" and "Could it ever become conscious?", but "What would be analogous to consciousness in the Web?" and "What can we learn by wondering whether such a thing could ever happen?" Those remain exciting and open questions.