Research team reproduces major functional principles of the brain using technology

July 1, 2016, Kiel University
The connected oscillators start to communicate with each other like in a neural network and become synchronised after a while until they all oscillate in the same rhythm as genuine neurons. Credit: Christian Urban, Kiel University

How does the human brain collect, process and store the flow of data which it constantly encounters? How does it manage cognitive tasks, which require complex interaction between various areas of the brain and overload high performance computers that work much more quickly? Why can the brain cope with all of this using much less energy? It is the aim of the research team from Kiel led by Professor Hermann Kohlstedt, Head of the Nanoelectronics Department at Kiel University (CAU) and spokesman of the national collaborative research project "Memristive devices for neural systems" (FOR 2093) funded by the German Research Foundation (DFG) to track this impressive efficiency of the human brain using technology and to implement its method of operation in artificial neural networks. The scientists from Kiel have now succeeded in electronically reproducing two fundamental principles of operation of the human brain, memory and synchronisation. They recently published their results in Applied Physics Letters.

The is a master of energy efficiency. It has approximately 100 billion nerve cells, also known as neurons, which manage with power of only about 20 Watt. Modern high performance computers would require many thousands of times more energy to perform similarly complex calculations as the brain manages. The neurons in the brain are linked to each other with synapses and form a highly complex network. The term "learning" in the neurological sense means that the synaptic connections in the brain are not determined statically. Instead they are continually readjusting on the basis of environmental influences, for example sensations. This makes it possible to store new memory content locally, known as the neurological plasticity of the brain.

In addition to the spatial ability of the neural connections to adjust, there is another important building block to process information in the brain: the synchronisation of neural groups. Electrical impulses, so-called action potentials, form the basic unit of information processing in the brain. These impulses permanently transmit information between the neurons and in doing so they cross and influence the synaptic connections in the brain. "In the case of conscious sensory perceptions the spatial irregular occurrence of neural impulses changes into ordered structures suddenly and for a limited time," says Professor Thorsten Bartsch, a neurologist at Kiel University and member of the research group. The previously independent impulses of the neurons synchronise themselves in this case even over areas of the brain that are not close together. Evidence of this synchronised "firing" in humans can also be shown by measuring brain waves (electroencephalography, EEG). "There have been discussions for a long time whether the human consciousness is closely linked with this synchronisation of the neural impulses. This may provide the key to gaining a better understanding of brain functions," continued Bartsch.

Tom Birkoben, Mirko Hansen and Marina Ignatov (from left to right) have developed an electrical circuit, which is in principle structured like human nerve cells. Credit: Christian Urban, Kiel University

The scientists based in Kiel have now reproduced both these principles of how the brain works, in other words storing memory content in the synapses and the synchronicity of the neural impulses within an electronic circuit. "We have used a new type of electronic device for this to help us reproduce the processes of the brain," explained Kohlstedt. These devices are described as memristors (from words "memory" and "resistor"). They are characterised by the fact that their electrical resistance depends on the charge that has flowed previously. "This method makes it possible to store different circumstances in biological networks, similar to "memory devices," added Dr. Martin Ziegler, a scientist in the Nanoelectronics Department and sub-project leader in the research group.

The researchers from Kiel have now coupled two oscillators to each other using memristors in their electronic circuit. Oscillators are switches, which generate periodic voltage impulses – similar to the "firing" of the neurons in the . At the start their impulses flowed in an asynchronous manner, with both oscillators therefore being uncoupled initially. Thanks to the adaptive "memory devices," their oscillations soon synchronised. This enabled the researchers to equip an electrical circuit with the same fundamental properties that also characterise a biological neural network.

Explore further: Physicists build "electronic synapses" for neural networks

More information: M. Ignatov et al. Synchronization of two memristively coupled van der Pol oscillators, Applied Physics Letters (2016). DOI: 10.1063/1.4942832

Related Stories

Physicists build "electronic synapses" for neural networks

April 20, 2016

A team of scientists from the Moscow Institute of Physics and Technology (MIPT) have created prototypes of "electronic synapses" based on ultra-thin films of hafnium oxide (HfO2). These prototypes could be used in fundamentally ...

Brain learning simulated via electronic replica memory

May 18, 2015

Scientists are attempting to mimic the memory and learning functions of neurons found in the human brain. To do so, they investigated the electronic equivalent of the synapse, the bridge, making it possible for neurons to ...

A network of artificial neurons learns to use human language

November 11, 2015

A group of researchers from the University of Sassari (Italy) and the University of Plymouth (UK) has developed a cognitive model, made up of two million interconnected artificial neurons, able to learn to communicate using ...

How the songbird learns its melody

June 21, 2016

Learning a first language is somewhat effortless. We start learning from our parents before we can even remember and the words and sounds are imprinted in our memory at an early age. Learning a new language as an adult is ...

The brain clock that keeps memories ticking

May 30, 2016

Just as members of an orchestra need a conductor to stay on tempo, neurons in the brain need well-timed waves of activity to organize memories across time. In the hippocampus—the brain's memory center—temporal ordering ...

Recommended for you

Trembling aspen leaves could save future Mars rovers

March 18, 2019

Researchers at the University of Warwick have been inspired by the unique movement of trembling aspen leaves, to devise an energy harvesting mechanism that could power weather sensors in hostile environments and could even ...

Quantum sensing method measures minuscule magnetic fields

March 15, 2019

A new way of measuring atomic-scale magnetic fields with great precision, not only up and down but sideways as well, has been developed by researchers at MIT. The new tool could be useful in applications as diverse as mapping ...

Researchers report new light-activated micro pump

March 11, 2019

Even the smallest mechanical pumps have limitations, from the complex microfabrication techniques required to make them to the fact that there are limits on how small they can be. Researchers have announced a potential solution—a ...

6 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Robert J_ Miskines
5 / 5 (2) Jul 01, 2016
We are just beginning our journey to understand the amazing structure and operation of the human brain. I commend this early work.
TehDog
5 / 5 (2) Jul 01, 2016
Shame memristor tech looks like it'll be dropped by HP, hopefully someone will pick it up and manage to drop the production cost to near commodity levels.
http://www.thereg...ath_row/
Whydening Gyre
1 / 5 (1) Jul 01, 2016
Shame memristor tech looks like it'll be dropped by HP, hopefully someone will pick it up and manage to drop the production cost to near commodity levels.

That is surprising news. Certainly, someone will find value in the technology.
I wonder if they will have to license it thru HP...
Blakut
5 / 5 (1) Jul 02, 2016
Article is fine but title sucks. Next we'll get "scientists use science to study the brain."
Mastoras
5 / 5 (1) Jul 29, 2016
I recall reading something similar since about..., 40 years ago. If memory serves me well, it must have been Hubert Dreyfus, "What computers can't do", first published in 1972. He later wrote another book, "What computers still can't do".
Mastoras
5 / 5 (1) Jul 29, 2016
My memory was mistaken. What I recall reading must have been:

Ross ASHBY "Design For A Brain", first published 1952

available online, also the previous I mention

1952!! I hadnt notice that. Back then I was just a highschool student. (So..., it was a bit more than 40 years!!)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.