What does the science of consciousness actually study?

By Prof. Si-Chen Lee, former President of National Taiwan University

I attended The Science of Consciousness international conference, held in Tucson, Arizona from 2 to 7 April 2018, and it gave me the chance to find out what the international scientific study of consciousness actually covers. Broadly, the papers fell into the following six themes: quantum biology, panpsychism, anesthetics and psychedelics, dreaming and sitting meditation, inner speech, and artificial intelligence.

1. Molecular and quantum biology
The physics of consciousness began to take shape in 1994, when the British physicist Roger Penrose and Stuart Hameroff, a physician at the University of Arizona, jointly proposed a physics of consciousness. They argued that the basis of consciousness lies not in the action potentials of nerve activity but in the matter of the microtubules that act as the cytoskeleton inside a neuron entering an ordered quantum state.

The walls of brain nerve cells are made up of many nanoscale tubules (around 14 nm) capable of forming quantum states. When sensory input enters the brain's neural network, an ordered quantum state arises, a superposition of different quantum states. As time passes, the external environment — gravity, for instance — affects how these quantum states evolve. Where the matter in different states is distributed across different regions of spacetime, the resulting difference in gravitational energy E equals the spacetime interval S between the two states (with physical constants such as the speed of light and the gravitational constant set to 1). At that point the superposition collapses and a single definite state appears. Consciousness, on their account, arises at this objective reduction (OR): when the spread of the quantum state produces a change in gravity that meets certain orchestrated conditions, the macroscopic quantum wave objectively collapses, a mechanism abbreviated as "Orch OR" and shown in Figure 1. In the instant the macroscopic quantum state collapses, consciousness in the brain arises; then a small portion of the microtubules begins to enter a quantum state once more and consciousness gradually fades, waiting for the next "Orch OR" event to produce new consciousness. On this picture the thoughts of the brain come in waves, one after another, over and over.

Penrose and his Orch OR model of consciousness

I think their model comes close to the nature of consciousness, though I would put one part the other way around: consciousness arises when the superposed quantum state forms, and disappears at objective reduction. Because a superposed quantum state is a complex-number state, at that moment imaginary-number consciousness scans into the architecture of the neural network that has entered the quantum state, producing the contents of consciousness — memory, thought, judgment, action. Sometimes experience buried in the neural network exerts a restraining force: do not act rashly, take this advice, hold back. Sometimes the quantum wave slips into the void and travels the spacetime of the universe, gathering inspiration and producing new ideas (see my article on complex spacetime). After the quantum wave objectively collapses, operation returns to real-number space and waits for the next ordered quantum state in the tubules — which is to say, for consciousness — to appear. Over more than 20 years of development and experimental exploration, more and more scholars have come to accept this model, and at this conference a good number of papers echoed the quantum model of consciousness from physiology, from philosophy, and even from molecular experiments on microtubules. There are dissenting scholars too, of course: the New York University philosopher David Chalmers challenged the "Orch OR" mechanism at this conference with a simple piece of logic, arguing that as an explanation of consciousness it is incomplete and needs revision. That fits the theory of consciousness I have proposed — consciousness arises only on entering the quantum state, and quantum collapse causes it to disappear — so after the conference I wrote to him in support of his reasoning and introduced my own model.

2. Panpsychism
More and more neuroscientists and philosophers are unconvinced by the materialist view that the physical brain comes first and that consciousness is a second-order property emerging from the workings of a complex neural network. They are beginning to believe instead that subjective feeling and awareness are basic properties of any object at all, and they have given these a name: "qualia". This view is called panpsychism, but it runs into three major difficulties:

(1) Do fundamental particles — quarks, electrons, atoms, molecules — have qualia? (2) How far do the "qualia" of these tiny atoms and molecules have to gather and grow in complexity before consciousness that can actually be experienced appears? This question is known as the combination problem. (3) How does the brain combine these primitive qualia into the consciousness each of us experiences?

3. Consciousness altered by anesthetics and psychedelics
Certain substances change a person's consciousness once they enter the body: anesthetics cause a loss of consciousness, while psychedelics such as DMT alter the state of consciousness and produce hallucinations. Studying how these molecules affect neural transmission in the brain, which receptors they bind to, and which regions they act on is therefore a great help in understanding how consciousness arises and where in the brain it arises. The preliminary conclusion is that these substances interrupt some of the long-range information links between neural networks. The brain ordinarily handles incoming information in a modular fashion, with feedback networks connecting the different modules, so consciousness is the result of those modular functions combining; anesthesia causes a loss of consciousness mainly because the feedback network is cut. Hallucination is a more complicated matter.

4. Research on dreaming and sitting meditation
Consciousness is lost in sleep, yet in dreaming it seems to become active again; likewise, it is less active during sitting meditation. Analyzing brainwaves in these states, or the changes in the resting-state network on magnetic resonance imaging of the brain, therefore allows a deeper understanding of the nature of consciousness.

5. Linguistics and inner speech
For most people it is the temporal lobe of the left hemisphere that governs language, and the motor area of the left hemisphere that controls the right hand; only about 1.5 percent of people have language governed by the right hemisphere. Since right-handers are the majority, movement and language end up competing for territory in the left hemisphere, and in a small proportion of people the language area is pushed apart into several scattered regions, or even moved across to the right hemisphere. This leads some people to hear an inner voice, as though someone were speaking to them, and to be diagnosed with a psychiatric illness — the price humanity pays for developing language.

6. Will AI develop consciousness?
Artificial intelligence is advancing at extraordinary speed. AlphaGo is already unbeatable at Go, having defeated the world champion, and many routine jobs will be taken over by machines. What worries people more is whether robots will develop consciousness like our own and put human survival at risk. The British physicist Roger Penrose, shown in Figure 1 and one of the two scientists who first proposed a physics of consciousness in 1994, thinks they will not, and he makes the point with a game of chess. The position is a draw, and anyone with a little chess experience can see it at a glance; but when he fed the position to the strongest chess programs, Deep Blue among them, they could not reach that conclusion, because the programmers had never considered this kind of drawn position. In other words, the program cannot judge for itself. From this he concludes that AI will not develop consciousness of its own accord. On my own model of consciousness, of course, AI does not enter a complex-number quantum state; no imaginary component appears, and so no consciousness is produced.