One of the most enduring mysteries that science struggles to explain is how does the mind think?
An article in this month’s Discover Magazine, in our office greeting room, proposes some very, very new way to answer how we think.
Mechanics v. Thought: Mechanics are by Wires
We know a lot about how the mechanics of the mind work. A nerve is like a wire and information is transmitted down the wire to make things happen, like move an arm, or slow down the pulse, or widen the eyes. All these actions involve an electrical signal sparking an muscle contraction.
All we need, really, to understand this system, is some sense of how an electrical signal is started in the nerve(s) of the brain, and how that signal is transmitted to the muscle. Current thinking about how the electrical signal is generated in a nerve and how it is transmitted to the muscle is based on the fact that all nerves have a tremendous electrical charge across their membranes. Charged ions are pumped in and out of the nerve cell, creating a potential charge ready to spark whenever the membrane is opened to the flow of the ions in and out of the cell. That flow of ions is like a controlled spark that can be propagated along the entire length of each neuron on the way to the muscle. Once received, we know quite a bit about how an electrical impulse turns into a muscle contraction.
In this concept of how the muscle is told to move, an electrical signal is generated in the brain, in a nerve, and the nerve acts like a wire, shooting current down its length, and down the length of connecting nerves, until the current sparks the contraction of the muscle.
Mechanics v. Thought: Thoughts are by Quanta
But this understanding of how nerves work has never succeeded in explaining how consciousness occurs. No one has ever located the set of nerves whose membrane firings create thought. Many, many have tried, no one has assembled a working model of a set of wires generating thinking.
Into this void has stepped a number of scientists who for many years have explored the notion that thought takes place by the actions described by quantum physics. The world of quantum physics is a world wholly alien to our fairly linear Newtonian minds. We tend to think that physics is all about items like billiard balls, well defined objects we can touch and see, that bounce in highly predictable ways, that allow us to know what will happen next after various interactions take place.
But in quantum physics, we are actually constrained, but the very nature of the objects and their energies, from knowing their position and speed entirely. In the world of quantum physics, an object can be in two places at the same time. Information can flow without moving. Events can leave traces that influence the next time events take place. Most of these wild and wonderful properties of the quantum world can only be observed in the world of the most tiny, where electrons, protons, and their subunits interact. We simply cannot, normally, see these strange properties of the quantum world in objects large enough for us to see, by eye or even microscope. This is because at the scale of the tiniest sub-atomic particle, all the wild and wonderful uncertainties of the quantum world define all that goes on. As you move from the tiny to the huge, so many of the uncertainties have combined into very, very set and predictable realities, that the world of predictable billiard ball motions prevails.
More and more, however, we are learning that biological decisions and events take place the tiny, tiny scale, where strange things not only can happen, but always to. Take the nerve signal, for example.
The nerve cell’s electrical signal takes place when ions move across the nerve membrane, which is getting to the scale of the quantum world.
An anesthesiologist from Arizona, Dr. Stuart Hameroff, asked a very simple question. During anesthesia, all the nerves that inform the brain of pain are firing away during surgery, just as they do when the patient is fully awake, but their is no perception of memory of pain during anesthesia. If the brain works by nerves firing electrical signals across their membranes, and those electrical signals are firing when you are under anesthesia, what brain function is turned off by anesthesia? He teamed up with the great philosopher-scientist, Dr. Roger Penrose, to propose that it was not the membrane of the nerve cell where thoughts are generated, but a set of tiny, tiny tubes found in every cell in every plant and animal, the microtubule.
Microtubules- the Heart of the Quantum Physics Model of Thinking
Microtubules are indeed micro, they are hollow pipes that have a diameter of 25 nanometers. The molecule that carries the smell of a fresh cookie, just one such molecule, is larger than 1 nanometer. So microtubules are indeed on the tiny, tiny scale. For most of their history, microtubules have been thought to give cells their shape, sort of a cellular skeleton. But it is also the case that subatomic particles come in and out of these tubes in a way, and at a small enough scale, that the quirky rules of quantum physics begin to act.
So the quantum theory of thinking, of consciousness, states that it is variations in subatomic particles inside a nerve cell, perhaps inside its microtubules, that generates, thought, leaves quantum traces that explain how memory is created, and creates consciousness.
Experiments have actually demonstrated that electrical signals within the microtubules of a nerve cell, occur at various frequencies of elecenergy, very much like a musical instrument produces various patterns of sound at various frequencies of vibration energy. Generate the right frequencies of energy, and the microtubules play patterns that can generate meaning and memory. Work conducted by Dr. Bandyopadhyay, a leading physicist, shows that if the right frequencies of energy are applied to a microtubule, it will resonate, generating an electrical signal thousands of times faster than the membrane of the nerve can.
This suggests that it is the microtubule where signals are generated, and that direct the generation of information along the nerve. We also know that anesthesia does impact the function of microtubules, which suggest they play a role in memory and thought, which are turned off by anesthesia.
Microtubules, Mind, and Music
Before going on, it is worth noting that the microtubules are tuned, just like a string on a piano, guitar, or violin. That is, only the right frequency of energy will result in them emitting a functional signal. At a very deep level, this is more evidence that music really does reflect our minds at play. If our minds, our very thoughts and emotions, are generated, not by firmly set wires, but by microtubules that are quite literally tuned to only generate signal at set frequencies, then thoughts are in reality musical.
Microtubules and Memory
It’s not just how we think that we have struggled to explain, it’s how we remember. No one has quite figured out how that happens in a set of nerves we think of as wires. There is good work done that shows the wires can be altered in their connections, and this does seem to explain how some thoughts remain in our minds stably over time. But the mystery of memory remains.
One of the most curious and odd properties of the world of quantum physics has to do with physical materials developing memories. The idea goes something like this. Take a set of tiny, tiny materials, such as bits of atoms, or even atoms, the realm where the rules of quantum mechanics define that world. In such a realm, if a current passes through these tiny, tiny items, it changes the electrical properties of these items. Thus, a experience of a current leaves a permanent change in the material, a memory of the event!
Research on building sets of tiny, tiny materials, that can retain memory of past currents passing through, is the leading edge of computer science. Such materials will one day require 1% of the energy of a regular memory device, the computer chip.
This quite odd property of quantum mechanics has actually been demonstrated in a lab. In the lab, a dish was filled with microtubules, and electrical current was passed through the material. The microtubules conducted electricity better than the usual salt water. And when electricity ran through the microtubules, their electrical properties changed, even when the electricity stopped. This is something that never happens in salt water. The lab physically demonstrated even a simple dish of microtubules has memory!
- We all wonder, how does our mind think, how does it remember? And most of us know, at some level, that no one knows the answer to this question. Curious that we all think, and know that we do, but don’t really know how.
- For the modern age, the dominant concept of how the brain works is that it consists of hundreds of billions of wires, that are very much the wires in our home and car. They are long strands of materials that transmit electrical signal. And it is the case that nerves do this, once activated, they shoot electrical signal to the next nerve or muscle.
- Nerves as wires explain much of how we move, how nerves talk to muscles and coordinate our motion.
- But the big wire concept has not explained how a 3 pound brain can generate the level of thought that we have.
- Now comes the shift, from wire to quantum mechanics. Tiny, tiny tubes in every cell of every animal and plant, the microtubules, allow atoms or parts of atoms to hum along their length, if their energy is tuned to that microtubule. These motions of atoms and subatoms allow for the strange rules of quantum physics to lead the way, to define, what happens.
- The quantum physics of microtubules is opening a path to seeing how our very small brains can have such a startling array and variety of thoughts and emotions. Signals from the microtubules need only 1% of the energy the large membranes of the nerve need to operate, and they generate signal thousands of times faster.
- Materials acting at the level of quantum mechanics have memory, which may explain how we have memory.
These new areas of understanding may help us unlock the great mysteries thinking, consciousness, and memory. In doing so, we may finally find ways to help our sore minds find comfort without harm. And, we may build thinking machines that can help us achieve new frontiers.
Finally, isn’t it rather extraordinary that at the very tiniest level, perhaps the level where thought, feeling, and memory actually come into being, sits a structure that works only by the rules of music?
To your health,
Dr. Arthur Lavin