Microchip Mimics Human Synapse!

According to a report in ScienceDaily, a newly developed microchip can imitate the brain's unique information processing in real time. Neuroinformatics researchers from the University of Zurich and ETH Zurich together with colleagues from the EU and US recently demonstrated how complex cognitive abilities can be incorporated into electronic systems made with so-called neuromorphic chips: They showed how to assemble and configure these electronic systems to function in a way similar to an actual human brain.

No computer works as efficiently as the human brain -- so much so that building an artificial brain is the goal of many scientists. Indeed, many futurists see the day when a computer will attain self-awareness, but that's a story for another time.

Neuroinformatics researchers from the University of Zurich and ETH Zurich have now made a breakthrough by understanding how to configure so-called neuromorphic chips to imitate the brain's information processing abilities in real-time. They demonstrated this by building an artificial sensory processing system that exhibits cognitive (thinking) abilities.

Most approaches in neuroinformatics are limited to the development of neural network models on conventional computers or aim to simulate complex nerve networks on supercomputers. All of these involve traditional binary computers with their on-off approach to logic. Few pursue the Zurich researchers' approach to develop electronic circuits that are comparable to a real brain in terms of size, speed, and energy consumption.

"Our goal is to emulate the properties of biological neurons and synapses directly on microchips... Thanks to our method, neuromorphic chips can be configured for a large class of behavior modes. Our results are pivotal for the development of new brain-inspired technologies.

One application, for instance, might be to combine the chips with sensory neuromorphic components, such as an artificial cochlea or retina, to create complex cognitive systems that interact with their surroundings in real time."
Giacomo Indiveri, Institute of Neuroinformatics (INI), University of Zurich and ETH Zurich.

The neuromorphic chips can take data and modulate the transmission of the impulses, make decisions based on short term memory and alter future responses to similar data (learn).

Other chips, memristors, can learn from experience!

Scientists have long been dreaming about building a computer that would work like a brain. This is because a brain is far more energy-saving than a computer, it can learn by itself, and it doesn't need any programming. Privatdozent [senior lecturer] Dr. Andy Thomas from Bielefeld University's Faculty of Physics is experimenting with memristors -- electronic microcomponents that imitate natural nerves.

Thomas and his colleagues have demonstrated that they could do this a year ago. They constructed a memristor that is capable of learning. Andy Thomas is now using his memristors as key components in a blueprint for an artificial brain.

Memristors are made of fine nanolayers and can be used to connect electric circuits. For several years now, the memristor has been considered to be the electronic equivalent of the synapse. Synapses are, so to speak, the bridges across which nerve cells (neurons) contact each other. Their connections increase in strength the more often they are used. Usually, one nerve cell is connected to other nerve cells across thousands of synapses.

Like synapses, memristors learn from earlier impulses. In their case, these are electrical impulses that (as yet) do not come from nerve cells but from the electric circuits to which they are connected. The amount of current a memristor allows to pass depends on how strong the current was that flowed through it in the past and how long it was exposed to it.

Explain it to me...

It is common to think of the human brain as a kind of super-computer. Certainly there are many analogies. Computers have the ability to store and remember information, to compare and even make decisions based on programmed instructions. But the mechanics of all computers is fundamentally a switch, or "gate", that either allows an electrical current to flow (on) or not (off).

Here is a great video that explains how the logic circuits work. You can skip this if you are not inclined to understand electrical circuits, etc.

While the brain's neurons and synapses perform a similar function in the brain, recent discoveries have revealed how unlike a computer this remarkable organ really is.

New discoveries shed light on the amazing abilities of our brains

Because most of our communication uses language, we have become used to expressing our thoughts in a linear progression; each idea is an expansion of the previous one. This logical sequence of data is also the foundation of computer programming languages. We envision computers as an extension of our own minds, and so we naturally try to understand our brain in the same mechanistic fashion.

The apparent magic of a computer processor is its ability to rapidly open and close a huge number of switches. In the early days these switches were actual relays, giving rise to the clicking sound that characterized brainiacs like Robbie the Robot [above] in the classic film, Forbidden Planet.

In 1946, two Americans, Presper Eckert, and John Mauchly built the ENIAC electronic computer which used silent vacuum tubes instead of the relays. A year later engineers, working at AT&T's Bell Labs, invented the diode transistor which would replace the vacuum tube forever. Miniturization and the development of micro-processors has made it possible for you to be reading this article on a powerful computer. Yet, as remarkable as this technology has become, computers are still just collections of more and faster on-off switches.

At school, I was taught that the brain also had switches -- about 500 trillion of them -- and they were called synapses. These are the gaps between neurons, or brain cells. Each synapse could open and close like a computer switch, allowing an electrical impulse to either continue or be inhibited. It was the same on-off model. This idea of a simple switch persists even now but it is about to change.

The synapse is no ordinary switch!

Synapses are tiny -- less than a thousandth of a millimeter in diameter -- so researchers have not been able to see exactly what goes on in these neural gaps. A team at Stanford University's School of Medicine has spent years engineering a new imaging model called array tomography. It's kind of like a CAT scan and an electron microscope combined. The "slices" of many scans are manipulated by a computer to form 3D images that can be rotated, penetrated, navigated and analysed.

The Stanford team took tissue samples from a mouse whose brain had been bioengineered to make larger neurons in the cerebral cortex express a fluorescent protein (found in jellyfish), making them glow yellow-green. Because of this glow, the researchers were able to see synapses against the background of neurons. When they used their array tomography to view the synapses, their revealed complexity was almost beyond belief.

To say that a synapse is much more than a switch is a gross understatement! The revelation of synaptic space has had the same effect upon neuroscientists as the Hubble Telescope has had on astronomers.

According to Stephen Smith, a professor of molecular and cellular physiology at Stanford:

"One synapse, by itself, is more like a microprocessor-- with both memory-storage and information-processing elements -- than a mere on/off switch. In fact, one synapse may contain on the order of 1,000 molecular-scale switches. A single human brain has more switches than all the computers and routers and Internet connections on Earth." -- Cnet.com

Mark Miller, a doctoral student at Brandeis University, stained thin slices of a mouses brain to show how neurons are connected to one another [above left]. The image shows three neuron cells (two yellow and one red) and their connections. The synapses are too small to be visible. The image on the right was developed by a group of astrophysicists, using a supercomputer, to simulate the origins and evolution of the universe. The bright clusters are full of galaxies, surrounded by thousands of stars, more galaxies and dark matter.

These similar phenomena are examples of fractal networks, where information and energy are distributed through a distinct pattern, interconnected on a microcosmic and macrocosmic scale. And the similarities are even more significant.

As we shall see, astrophysicists are just now moving away from the gravitational model in favor of theories that consider electric fields and plasma as the new paradigm (the so-called "electric universe") to explain the evolution and maintenance of our universe. Neuroscientists are also beginning to experience their own paradigm shifts from "brain switches" to electric field theories!

But wait... there's more!

While the immensely complex synapse was still causing slack jaws, neuroscientists uncovered strong evidence that neurons also communicate with each other through weak electric fields. The study, published in the journal Nature Neuroscience, by Dr Costas Anastassiou (Caltech), explains how every time an electrical impulse races down the branch of a neuron, a tiny electric field surrounds that cell. This phenomenon was expected, since any conductor carrying an electrical current generates a field. But until now, the significance of this neuron field was thought to be negligible. The focus in neurology has always been on the end of the neuron -- the synapse -- where the mechanistic "switch" model explained neural communication so well.

"I think this is a very exciting new discovery. We knew that weak electric fields can impact brain activity, but what no one had really tested before was whether electric fields produced by the brain itself can influence its own activity." --Ole Paulsen, a neuroscientist at the University of Cambridge

The Caltech study showed that when just a few neurons were generating electrical fields, the effects were hardly noticeable. But when a group of neurons fire together, their collective fields were very significant, functioning to coordinate, accelerate and potentiate the neural activity.

"We observed that fields as weak as one millivolt per millimetre robustly alter the firing of individual neurons, and increase the so-called 'spike-field coherence' -- the synchronicity with which neurons fire with relationship to the field.

Increased spike-field coherency may substantially enhance the amount of information transmitted between neurons as well as increase its reliability.

I firmly believe that understanding the origin and functionality of endogenous brain fields will lead to several revelations regarding information processing at the circuit level, which, in my opinion, is the level at which perceptions and concepts arise." -- Dr. Anastassiou

Fields of a different kind -- Pastures and Morphogenetic

One of the amazing things about the brain is its intelligence -- the ability to learn. It's looking more like learning is influenced as much by electric fields as the alterations of synaptic connections.

The image above shows the tracks of cattle in a field with a water hole. It's likely that the first cattle stumbled upon the water by chance, leaving a noticeable trail in the dirt. As more animals sought water, they tended to follow established paths -- even when these paths were not the most direct route. Over time, the most travelled paths parallel each other, defining the most efficient routes to the water hole.

The brain establishes neural paths when it learns. Repetition helps us learn a task because, like the cattle seeking water, it causes multiple paths to be established between the neurons and synapses. The multiple paths collectively increase the electrical fields which, in turn, potentiate and enhance the more efficient flow of information.

This "field effect" may prove to be more significant in explaining learning, habits and addiction than the current model of neural reconfiguration. It explains how thoughts are not singular facts but can be layered, associated and integrated with other paths containing ideas, memories and feelings. Groups of paths are stimulated by the neural field, resulting in a variety of novel thoughts. While a computer made of switches is incapable of creativity, our brain most certainly is.

Like in astronomy, understanding the effects of electrical fields is an immature science. Perhaps when we understand more of how this works on the macro-scale we will be able to unlock more secrets inside our brain.

Morphogenetic Fields are another mystery that begs for an explanation.

Rupert Sheldrake [right] is a biochemist who has been a pioneer in something he termed the morphogenetic field. Sheldrake postulated that there was some type of memory or data that could exist outside of an organism and would serve the same role of enhancing intracellular communication that neuroscientists are finding in the brain. But Sheldrake envisioned the morphogenetic field decades earlier and applied it to a myriad of living tissue.

He based his premise on the developing embryo which starts out as a single cell. As it evolves, cells differentiate to form various types of tissue and organs. Embryology explains this cell differentiation in terms of DNA, but it seems an incredibly complex and remarkably stable achievement for a molecule. How are all of the cells made to work together after they are formed? How do they communicate with each other?

For Sheldrake the answer was an invisible but very real biological field that coordinates living cells, promoting their cooperation and unifying them to form a single organism. He described cells of a similar type as having a specific "resonance" which helps them to maintain -- rather than deviate from -- their designed function.

Later, Sheldrake extended his morphogenetic field theory to describe how individual organisms resonate with each other, sharing experiences and learned behavior that enhances their survival.

Here is a good video where Sheldrake explains his Morphogenetic Field theory in detail:

The 100th Monkey!

The Japanese monkey, Macaca Fuscata [right], lives on the island of Koshima and has been the target of biologists social scientists for decades. To keep them viable, they are routinely given sweet potatoes which are dropped on the beach. The monkeys enjoyed the potatoes but obviously disliked the sand that clung to them.

One day, perhaps by accident, an 18 month monkey brought a potato to a nearby stream where the water washed the sand off. Her siblings observed this and started to routinely wash their potatoes also. Scientists watched as the immediate family group, then friends of the family, began to practice this washing technique. It was a slow evolution and a majority of the other monkeys still coped with the unpleasant sand on their potatoes.

Within six years, all of the young monkeys had learned to wash the sand off their sweet potatoes. Some adults who imitated their children also learned this technique. But most adults kept eating the dirty sweet potatoes.

Then something startling took place. After a certain number of Koshima monkeys had started washing their sweet potatoes (the scientists estimate about 100) -- suddenly everyone in the tribe was washing their sweet potatoes before eating them. Scientists could not explain the almost instantaneous change in behavior. Even more remarkable, colonies of the same species on different islands -- who had never been exposed to the washing technique -- suddenly began washing their potatoes! Sheldrake interpreted this behavior to the morphogenetic field, explaining that when a certain critical number of a species adapts, that adaptation will be contained and proliferated by the field. It's a kind of collective unconscious.

Scientists were quick to jump all over Sheldrake because his theory was not mechanistic. It relied on something that defied measurement or physical explanation. But Sheldrake accepted a challenge to demonstrate his theory in a now famous BBC televised experiment.

The Experiment - What do YOU see?

"The experiment has three steps. You start by showing two of these puzzle pictures to a group of test subjects to establish a base line for how easily the hidden picture in each can be recognized.

Next, on TV so that you can reach large numbers of people, you teach the TV viewers how to see one of the hidden images, but do not show the other.

Finally, you get a new group of test subjects who did not see or hear about the TV show, and again test their ability to recognize the hidden images. The experimental question is, if lots of people learn to spot the hidden image in the puzzle picture, then does that make it easier for other people to spot it as well?" -- Sheldrake

The people who saw the television show and were shown how to interpret the image in the pictures (i.e. looking at the negative, white space) are like the critical number (the "100 monkeys") who learned to wash their sweet potatoes. This knowledge then goes in to the morphogenetic field and becomes assessable to large numbers of people who did not watch the televised show and were not shown how to interpret the pictures. You compare the successful results of a groups, before and after the method of interpretation was taught, to see the effect.

Below are the two images shown to BBC viewers in the experiment. Try to guess what the picture is in each puzzle. After you click on the first picture, the hidden image will be revealed. Using that knowledge, can you "see" the image in the second picture? Click after you have made a guess. How did you do?

Figure 1 [above]

Figure 2 [above]

The first of these TV experiments was done in Britain in 1983 with 2 million viewers. Several thousand people were then tested in different parts of the world and the result was very positive and significant.

"This was then done on a larger scale on BBC television in 1984 with 8 million viewers. It was on one of the popular science programs called Tomorrow's World. Now in that one, the image to be shown was selected at random, live, at the moment of broadcast.

Post-broadcast tests were then carried out in North America, in Western Europe, and in the Southern Hemisphere, particularly South Africa ... The percentage of people recognizing the hidden image in the picture that was shown on television increased very significantly in Western Europe, but not in North America, and in neither case was there a change in the control picture.

So there seems to have been an effect, but the effect was confined to Western Europe.

Now at first this looks as if it might be a distance effect but I don't expect distance effects ... one possibility is that this has to do with people being in similar time zones, being more in phase. South Africa and Western Europe are only one hour different from Britain, whereas America is 5 to 8 hours different." -- Sheldrake

The Plastic Brain

When we speak of the brain being "plastic" we are speaking about its ability to reorganize the neurons to perform different functions, as needed. If one part of the brain is injured, it is possible for other parts of the brain to be mobilized to compensate for the lost tissue. As we age, it is possible for individual neurons to regenerate and be revitalized. More evidence is suggesting that electrical fields play an important role in this "plasticity".

Neurons are continually born from endogenous stem cells and added to the brain throughout our lives. But as we get older, the development of new neurons declines dramatically. A study reported in the Annals of Neurology in 2002 described how aged mice with minimal new neuron development were revitalized and their neurons made to regenerate up to five times that of the control group merely by subjecting them to robust mental stimuli.

"Could this plastic response be relevant for explaining the beneficial effects of leading 'an active life' on brain function and pathology? Adult hippocampal neurogenesis in mice living in an enriched environment from the age of 10 to 20 months was fivefold higher than in controls.

This cellular plasticity occurred in the context of significant improvements of learning parameters, exploratory behavior, and locomotor activity. Enriched living mice also had a reduced lipofuscin load in the dentate gyrus, indicating decreased nonspecific age-dependent degeneration. Therefore, in mice signs of neuronal aging can be diminished by a sustained active and challenging life, even if this stimulation started only at medium age. Activity exerts not only an acute but also a sustained effect on brain plasticity." -- [2]

It seems probable that by activating existing paths and stimulating electric field activity, neurogenesis -- the revitalization of neurons -- can be achieved. There seems to be some kind of mechanism that switches on the genes, making them behave as if they were younger. The good news is that this revitalization does not need to be intellectual. Brain stimulation from ordinary physical exercise appears to have the same effect.

In UCLA's Division of Neurosurgery, researchers found that rodents who were exercised regularly had greater neurogenesis and neuroplasticity compared to a control group that was not able to exercise. [3] So it seems that multi-path stimulation is key to maintaining a healthy brain. And this plasticity again appears related to the electric fields that are generated when a collection of neural pathways are stimulated simultaneously.

Can we mould our own brain?

Yes. Check out a guy who has developed his brain such that he remembers EVERYTHING!

This is, of course, a dramatic example. But we all have reconfigured brains to some extent. Anything that you do repeatedly, or acquire a skill at doing, is indicative of a specialization and alteration in brain tissue. One of the more interesting examples is that of musicians.

CONTINUED: The Brains of Musicians

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