Can a lobster feel pain in the same way as you or me?
We know that they have the same sensors – the so-called nociceptors – that make us cry when hurt. And they certainly behave as if they feel something unpleasant. For example, when a cook places them in boiling water, they shrug their tails as if in agony.
But are they really aware of the sensation? Or is this answer just a reflex?
When you or I perform an action, our mind is filled with a complex conscious experience. We can not just assume that this also applies to other animals – especially animals with such different brains. It is quite possible – some scientists even claim that it is likely ̵
"With a dog that behaves very much like us who is in a body that is not too different from our body, and whose brain is not too different from our body, is much more plausible when he does Seeing and hearing things as we do, saying that this is the case is, so to speak, completely "dark inside," says Giulio Tononi, a neuroscientist at the University of Wisconsin-Madison. "But when it comes to a lobster, all bets are off."
The question of whether other brains that are alien to us are capable of awareness is just one of the many puzzles that arise when scientists begin to think about consciousness. When does the brain become conscious of our own being for the first time? Why does it feel that way? And will computers ever be able to achieve the same inner life?
Tononi may have a solution to these puzzles. His "Integrated Information Theory" is one of the most exciting theories of consciousness that have emerged in recent years, and although it has not yet been proven, it provides some testable hypotheses that can soon provide a definitive answer.
Knowing what Consciousness is and how it came about is crucial to understanding our place in the universe and what we do with our lives – Giulio Tononi
Tononi says his fascination with being a teenager typically youthful "employment with ethics and philosophy developed. "I have realized that it is important to know what consciousness is and how it came about to understand our place in the universe and what we do with our lives," he says.
At this age, he did not know the best way to follow these questions – would it be mathematics? Or philosophy? – but finally he chose medicine. And the clinical experience helped to fertilize his young mind. "It's really something special to be directly exposed to neurological and psychotic cases," he says. "It really forces you to deal directly with what happens to patients when they lose consciousness or lose the constituents of consciousness in a way that is really hard to imagine if you have not seen this actually happen. "
In his published study, however, he built his reputation by pioneering sleep – a less controversial field. "At that time you could not even talk about consciousness," he says. However, he kept thinking, and in 2004 he published his first repetition of his theory.
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It begins with a series of axioms that define consciousness is actually . Tononi suggests that every conscious experience must be structured – when you look at the space around you, you can distinguish the position of objects relative to one another. It is also differentiated specifically and " " – each experience will be different depending on the particular circumstances, which means that there is a large number of possible experiences. And it is integrated . When you look at a red book on a table, shape, color, and location – though initially processed separately in the brain – are held together in one single conscious experience. We even combine information from many different senses – what Virginia Woolf has called the "perpetual shower of countless atoms" to a single meaning of the here and now.
According to Tononi's theory, more information is shared between them and processes many different components, the higher the state of consciousness.
From these axioms, Tononi suggests we take the consciousness of a person (or an animal, or even a computer) into account Brain can identify possible "information integration" (or CPU). In his theory, the more information that is exchanged and processed between many different components to contribute to that single experience, the higher the level of consciousness.
The best way to understand what this means in practice is to compare the brain visual system to a digital camera. A camera captures the light that falls on each pixel of the image sensor. This is clearly a huge amount of information. However, the pixels do not 'talk' or share information: each of them independently records a tiny portion of the scene. And without this integration, she can not have rich conscious experiences.
Like the digital camera, the human retina contains many sensors that initially capture small elements of the scene. These data are then shared and processed in many different brain regions. In some areas, the colors are being worked on, and the raw data is being adjusted so that the light levels make sense, so that colors can be recognized even under very different conditions. Others examine the contours, which could cause the parts of an object to be obscured-for example, if there's a coffee cup in front of a part of the book-so you still have a sense of the overall shape. These regions will then pass this information on to bring them further into the hierarchy, to combine the different elements – and to evoke the conscious experience of everything that is before us.
The same goes for our memories. Unlike a photo library of a digital camera, we do not store every experience separately. They are combined and networked into a meaningful narrative. Every time we experience something new, it is integrated into this previous information. That's why the taste of a single madeleina can spark a memory of our distant childhood – and that's all part of our conscious experience.
At least that's the theory – and this is consistent with many medical observations and experiments
By changing the levels of important neurotransmitters, anesthesia seems to break down the informational integration of the brain
A study published in 2015 examined the brains of participants various forms of anesthesia – including propofol and xenon. To get an idea of the brain's ability to integrate information, the team has created a magnetic field over the scalp to stimulate a small area of the underlying cortex – a non-invasive standard method called Transcranial Magnetic Stimulation (TMS) becomes. If you are awake, you would observe a complex wave of activity as the brain responds to the TMS, with many different regions responding to it, which Tononi regards as an indication of the information integration between the different groups of neurons.
But the brains of people under propofol and xenon did not show this response – the brain waves produced were much simpler in form than the bustle of activity in the awakened brain. By altering the level of important neurotransmitters, the drugs appeared to have "broken down" the informational integration of the brain – this corresponded to the complete loss of consciousness of the participants during the experiment. Her inner experience had gone black.
For further comparison, the team also examined participants on ketamine. Although the drug does not address you to the outside world – which means it's also used as an anesthetic – patients often report wild dreams, as opposed to the pure "blank" experienced with propofol or xenon. In fact, Tononi's team found that responses to TMS were far more complex than those of other anesthetics, reflecting their altered state of consciousness. They were not connected to the outside world, but during their drugged fantasies, their thoughts were still very excited.
Tononi found similar results in the study of different stages of sleep. During non-REM sleep – where dreams are rarer – responses to TMS were less complex. However, during REM sleep, which often coincides with dream consciousness, information integration seemed to be higher.
He emphasizes that this is not "proof" that his theory is correct, but it shows that he could work right lines. "Suppose that if we had achieved the opposite result, we would have got in trouble."
Some people do not have a cerebellum that contains half of the neurons in the entire brain, but they are still capable of conscious perception.
Tononi Theoretically, the experience of people with different forms of brain damage also plays a role. The cerebellum is, for example, the walnut-shaped, pink-gray mass at the base of the brain, whose main task is to coordinate our movements. It contains four times as many neurons as the cortex, the bark-like outer layer of the brain – about half the total number of neurons in the entire brain. However, some people lack a cerebellum (either because they were born without or lost through brain damage), and they are still capable of conscious perception and lead a relatively long and "normal" life without loss of consciousness.
These cases would not make sense if you consider only the sheer number of neurons important for creating conscious experience. However, in accordance with Tononi's theory, cerebellar processing is mostly local instead of exchanging and integrating signals, meaning that it plays a minimal role in consciousness.
Measurements of brain responses to TMS also appear to predict patient awareness in a noncommunicative and vegetative state – a finding with potentially profound clinical applications.
Big claims, of course, require great evidence – and few scientific questions are deeper than the mystery of consciousness.
Tononi's previous methods provide a very crude "representation" of the information integration of the brain – and to really prove his theory, more sophisticated tools are needed to accurately measure the processing in each brain.
Daniel Toker, neuroscientist at the University of California Berkeley, says the idea that integrating information is necessary for consciousness is very "intuitive" for other SCs, but much more evidence is needed. "The broader perspective in this area is that it's an interesting idea, but pretty much unchecked," he says.
It all depends on mathematics. Using prior techniques, the time it takes to measure information integration in a network increases with the number of nodes you consider "extremely exponential." This means that even with the best technology, the calculation can take longer than the lifetime of the universe. However, Toker has recently come up with a clever shortcut for these calculations, which may take a few minutes to test with measurements on a few macaques. This could be a first step to put the theory on a much firmer experimental basis. "We're really at an early stage," says Toker.
Only then can we begin to answer the really big questions – for example, to compare the consciousness of different types of brain. Although Tononi's theory is not correct, Toker believes that he has helped make other neuroscientists think more mathematically about the issue of consciousness – which could inspire future theories.
If the integrated information theory is right, computers could do that behave just like you and me, and yet there would be literally nobody there – Giulio Tononi
And if the theory of information integration were correct, this would really be a game, that goes far beyond neuroscience and medicine. Evidence of consciousness in a creature like a lobster, for example, could change the fight for animal rights.
He would also answer some long-standing questions about artificial intelligence. Tononi argues that the basic architecture of the computers we have today – which consist of networks of transistors – precludes the necessary level of information integration necessary for consciousness. Even if they can be programmed to behave like humans, they would never have our rich inner lives.
"Some say that computers can be as good cognitively as we are sooner rather than later – not just in some tasks, such as playing games, playing chess or recognizing faces or driving cars, but everything," says Tononi. "But if integrated information theory is right, computers could behave just like you and me – in fact you [even] could be able to have a conversation with them that is as rewarding or rewarding as with you or me – and but there literally nobody would be there. "Again, it's about the question of whether intelligent behavior needs to emerge from consciousness – and Tononi's theory would not call that true. It could help us to understand how large bodies of people begin to think, feel, themselves as a unity to remember, to decide and to react
He stresses that this is not just a matter of computing power or the software used. "The physical architecture is always more or less the same, and that is not conducive to consciousness at all." Fortunately, the moral dilemmas seen in series such as Humans and Westworld can never become reality.
It could even help us to understand the way we interact with each other. Thomas Malone, director of the Center for Collective Intelligence at the Massachusetts Institute of Technology and author of the book Superminds, has recently applied the theory to teams of people – in the lab and in practice, including publishers of Wikipedia entries. He has shown that the estimates of the integrated information shared by the team members can predict the group performance for the different tasks. Although the concept of "group consciousness" seems like a vastness, he believes Tononi's theory could help us to understand how large bodies of people sometimes start to think, feel, decide, decide, and act as a unit.
Hey, caution: This is still very speculated: First, we need to make sure that integrated information is a consciousness symbol of the individual. "But I think it's very interesting to consider what this could mean when groups can become aware."
We still can not be sure whether a lobster, a computer or even a society is conscious or not But in the future, Tononi's theory can help us understand the "thoughts" that are very foreign to our own.
David Robson is senior journalist at BBC Future. He is @d_a_robson on Twitter. This piece contains original artwork by Emmanuel Lafont, an Argetina-born visual artist currently working in Spain.
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