Corporate Banner
Satellite Banner
Scientific Communities
Become a Member | Sign in
Home>News>This Article

Stanford Bioengineers Create Circuit Board Modeled on the Human Brain

Published: Wednesday, April 30, 2014
Last Updated: Wednesday, April 30, 2014
Bookmark and Share
Development offers greater possibilities for advances in robotics and a new way of understanding the brain.

Stanford bioengineers have developed a new circuit board modeled on the human brain, possibly opening up new frontiers in robotics and computing.

For all their sophistication, computers pale in comparison to the brain. The modest cortex of the mouse, for instance, operates 9,000 times faster than a personal computer simulation of its functions.

Not only is the PC slower, it takes 40,000 times more power to run, writes Kwabena Boahen, associate professor of bioengineering at Stanford, in an article for the Proceedings of the IEEE.

"From a pure energy perspective, the brain is hard to match," says Boahen, whose article surveys how "neuromorphic" researchers in the United States and Europe are using silicon and software to build electronic systems that mimic neurons and synapses.

Boahen and his team have developed Neurogrid, a circuit board consisting of 16 custom-designed "Neurocore" chips. Together these 16 chips can simulate 1 million neurons and billions of synaptic connections. The team designed these chips with power efficiency in mind. Their strategy was to enable certain synapses to share hardware circuits. The result was Neurogrid – a device about the size of an iPad that can simulate orders of magnitude more neurons and synapses than other brain mimics on the power it takes to run a tablet computer.

The National Institutes of Health funded development of this million-neuron prototype with a five-year Pioneer Award. Now Boahen stands ready for the next steps – lowering costs and creating compiler software that would enable engineers and computer scientists with no knowledge of neuroscience to solve problems – such as controlling a humanoid robot – using Neurogrid.

Its speed and low power characteristics make Neurogrid ideal for more than just modeling the human brain. Boahen is working with other Stanford scientists to develop prosthetic limbs for paralyzed people that would be controlled by a Neurocore-like chip.

"Right now, you have to know how the brain works to program one of these," said Boahen, gesturing at the $40,000 prototype board on the desk of his Stanford office. "We want to create a neurocompiler so that you would not need to know anything about synapses and neurons to able to use one of these."

Brain ferment
In his article, Boahen notes the larger context of neuromorphic research, including the European Union's Human Brain Project, which aims to simulate a human brain on a supercomputer. By contrast, the U.S. BRAIN Project – short for Brain Research through Advancing Innovative Neurotechnologies – has taken a tool-building approach by challenging scientists, including many at Stanford, to develop new kinds of tools that can read out the activity of thousands or even millions of neurons in the brain as well as write in complex patterns of activity.

Zooming from the big picture, Boahen's article focuses on two projects comparable to Neurogrid that attempt to model brain functions in silicon and/or software.

One of these efforts is IBM's SyNAPSE Project – short for Systems of Neuromorphic Adaptive Plastic Scalable Electronics. As the name implies, SyNAPSE involves a bid to redesign chips, code-named Golden Gate, to emulate the ability of neurons to make a great many synaptic connections – a feature that helps the brain solve problems on the fly. At present a Golden Gate chip consists of 256 digital neurons each equipped with 1,024 digital synaptic circuits, with IBM on track to greatly increase the numbers of neurons in the system.

Heidelberg University's BrainScales project has the ambitious goal of developing analog chips to mimic the behaviors of neurons and synapses. Their HICANN chip – short for High Input Count Analog Neural Network – would be the core of a system designed to accelerate brain simulations, to enable researchers to model drug interactions that might take months to play out in a compressed time frame. At present, the HICANN system can emulate 512 neurons each equipped with 224 synaptic circuits, with a roadmap to greatly expand that hardware base.

Each of these research teams has made different technical choices, such as whether to dedicate each hardware circuit to modeling a single neural element (e.g., a single synapse) or several (e.g., by activating the hardware circuit twice to model the effect of two active synapses). These choices have resulted in different trade-offs in terms of capability and performance.

In his analysis, Boahen creates a single metric to account for total system cost – including the size of the chip, how many neurons it simulates and the power it consumes.

Neurogrid was by far the most cost-effective way to simulate neurons, in keeping with Boahen's goal of creating a system affordable enough to be widely used in research.

Speed and efficiency
But much work lies ahead. Each of the current million-neuron Neurogrid circuit boards cost about $40,000. Boahen believes dramatic cost reductions are possible. Neurogrid is based on 16 Neurocores, each of which supports 65,536 neurons. Those chips were made using 15-year-old fabrication technologies.

By switching to modern manufacturing processes and fabricating the chips in large volumes, he could cut a Neurocore's cost 100-fold – suggesting a million-neuron board for $400 a copy. With that cheaper hardware and compiler software to make it easy to configure, these neuromorphic systems could find numerous applications.

For instance, a chip as fast and efficient as the human brain could drive prosthetic limbs with the speed and complexity of our own actions – but without being tethered to a power source. Krishna Shenoy, an electrical engineering professor at Stanford and Boahen's neighbor at the interdisciplinary Bio-X center, is developing ways of reading brain signals to understand movement. Boahen envisions a Neurocore-like chip that could be implanted in a paralyzed person's brain, interpreting those intended movements and translating them to commands for prosthetic limbs without overheating the brain.

A small prosthetic arm in Boahen's lab is currently controlled by Neurogrid to execute movement commands in real time. For now it doesn't look like much, but its simple levers and joints hold hope for robotic limbs of the future.

Of course, all of these neuromorphic efforts are beggared by the complexity and efficiency of the human brain.

In his article, Boahen notes that Neurogrid is about 100,000 times more energy efficient than a personal computer simulation of 1 million neurons. Yet it is an energy hog compared to our biological CPU.

"The human brain, with 80,000 times more neurons than Neurogrid, consumes only three times as much power," Boahen writes. "Achieving this level of energy efficiency while offering greater configurability and scale is the ultimate challenge neuromorphic engineers face."

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,800+ scientific posters on ePosters
  • More Than 4,000+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

New Class of RNA Tumor Suppressors Identified
Two short, “housekeeping” RNA molecules block cancer growth by binding to an important cancer-associated protein called KRAS. More than a quarter of all human cancers are missing these RNAs.
Thursday, November 26, 2015
Ancient Viral Molecules Essential for Human Development
Genetic material from ancient viral infections is critical to human development, according to researchers at the Stanford University School of Medicine.
Wednesday, November 25, 2015
Sleep Deprivation Affects Stem Cells, Reducing Transplant Efficiency
Although the research was done in mice, the findings have possible implications for bone marrow transplants, more properly called hematopoietic stem cell transplants, in humans.
Friday, October 16, 2015
Enzyme Malfunction May be Why Binge Drinking Can Lead to Alcoholism
A new study in mice shows that restoring the synthesis of a key brain chemical tied to inhibiting addictive behavior may help prevent alcohol cravings following binge drinking.
Friday, October 09, 2015
How Cell Growth Triggers Cell Division
Researchers in Jan Skotheim's lab have discovered a previously unknown mechanism that controls how large cells grow, an insight that could one day provide insight into attacking diseases such as cancer.
Wednesday, October 07, 2015
Tension Helps Heart Cells Develop Normally in the Lab
Stanford engineers have uncovered the important role tension plays in growing heart cells out of the body.
Monday, October 05, 2015
Drug Disarms Deadly C. difficile Bacteria Without Destroying Healthy Gut Flora
A drug that blocks the intestinal pathogen without killing resident, beneficial microbes may prove superior to antibiotics, currently the front-line treatment for the infection.
Friday, September 25, 2015
Virus Re-Engineered to Deliver Targeted Therapies
Researchers stripped a virus of its infectious machinery and turned its benign core into a delivery vehicle that can target sick cells while leaving healthy tissue alone.
Thursday, September 24, 2015
Combination Drug Therapy Shrinks Pancreatic Tumors In Mice
Two drugs that affect the structure and function of DNA have been found to block the growth of pancreatic tumor cells in mice, researchers hope the drugs can soon be tested in humans with the disease.
Thursday, September 24, 2015
Delivering Missing Protein Heals Damaged Hearts in Animals
Researchers have discovered that a particular protein, Fstl1, plays a key role in regenerating dead heart-muscle cells.
Tuesday, September 22, 2015
Key Mechanism in Gene Expression Discovered
RNA polymerase II makes life possible by expressing genes. Now, a team of Stanford biologists, chemists and applied physicists has observed it at work in real time.
Thursday, September 17, 2015
Drug Prevents Type 1 Diabetes In Mice
A compound that blocks the synthesis of hyaluronan, a substance generally found in in all body tissue, protected mice from getting Type 1 diabetes. The compound is already approved in Europe and Asia for the treatment of gallbladder disease.
Wednesday, September 16, 2015
New Method for Producing Vital Cancer Drug
Stanford scientists produced a common cancer drug – previously only available from an endangered plant – in a common laboratory plant.
Tuesday, September 15, 2015
Scientists Home In On Origin Of Human, Chimpanzee Facial Differences
A study of species-specific regulation of gene expression in chimps and humans has identified regions important in human facial development and variation.
Monday, September 14, 2015
X-ray Laser Experiment Could Help in Designing Drugs for Brain Disorders
Scientists found that when two protein structures in the brain join up, they act as an amplifier for a slight increase in calcium concentration, triggering a gunshot-like release of neurotransmitters from one neuron to another.
Monday, August 24, 2015
Scientific News
High Throughput Mass Spectrometry-Based Screening Assay Trends
Dr John Comley provides an insight into HT MS-based screening with a focus on future user requirements and preferences.
The MaxSignal Colistin ELISA Test Kit from Bioo Scientific
Kit can help prevent the antibiotic apocalypse by keeping last resort drugs out of the food supply.
"Good" Mozzie Virus Might Hold Key to Fighting Human Disease
Australian scientists have discovered a new virus carried by one of the country’s most common pest mosquitoes.
Non-Disease Proteins Kill Brain Cells
Scientists at the forefront of cutting-edge research into neurodegenerative diseases such as Alzheimer’s and Parkinson’s have shown that the mere presence of protein aggregates may be as important as their form and identity in inducing cell death in brain tissue.
Closing the Loop on an HIV Escape Mechanism
Research team finds that protein motions regulate virus infectivity.
New Class of RNA Tumor Suppressors Identified
Two short, “housekeeping” RNA molecules block cancer growth by binding to an important cancer-associated protein called KRAS. More than a quarter of all human cancers are missing these RNAs.
Potential Treatment for Life-Threatening Viral Infections Revealed
The findings point to new therapies for Dengue, West Nile and Ebola.
World’s First Therapeutic Venom Database
Open-source library describes nearly 43,000 effects on the human body.
Biologists Induce Flatworms to Grow Heads and Brains of Other Species
Findings shed light on role of a new kind of epigenetic signaling in evolution, could yield clues for understanding birth defects and regeneration.
Fat Cells Originating from Bone Marrow Found in Humans
Cells could contribute to diabetes, heart disease.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,800+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,000+ scientific videos