Op Vimeo is een 11 minuten durende documentaire te zien, gemaakt door Erik Verheij en Tom Meulendijks, studenten Communicatie en Multimediadesign van Hogeschool Zuyd, Maastricht.

(R)Evolution. A documentary about transhumanism and evolution. Does the step to transhumanism mean the end of evolution?

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Circular polarization (credit: Wikipedia Commons)

Scientists at the Colorado School of Mines (CSM) and ITN Energy Systems have developed a new circular polarization filter with the potential to aid in early cancer detection, enhance vision through dust and clouds, and even improve a moviegoer’s 3D experience.

Polarization is the process by which rays of light exhibit different properties in different directions, but especially the state in which all the vibration or frequency of the light takes place in one visual plane.

When measuring the different properties of light, the human eye can, of course, see in color but it cannot differentiate between the inherently different polarizations of light emanating from an object. This new filter allows users to measure the polarization state of light quickly and efficiently.

Circular micropolarizer

“This is by far the easiest circular micropolarizer to fabricate, which lets us measure all of the properties of light using a simple camera,” notes  ITN researcher Dr. Russell Hollingsworth.

To better understand this new technique, consider the modern digital camera. Color digital cameras are made possible because of the development of micro-color filters that are put directly on the charge-coupled device chip within the camera, where each “pixel” is actually 3 or 4 independent pixels that detect a different discreet color.

The same concept is employed for this new approach to polarization — also using a simple digital camera — but there is also an added benefit. Not only does this new filter distinguish colors, it also measures both linear and circular polarized light.

Photographers are familiar with polarization filters you attach in front of your camera lens to decrease glare. But being able to make micropolarizers right on top of the detector array would result in a “polarization camera” that collects information in the same way color digital cameras do.

While linear polarizer filters are easy to make, circular polarizers, up to this point, have been very difficult to fabricate, but this problem may have been solved. The CSM/ITN research team developed a micro-structure that accurately measures circularly polarized light, the key to making a true polarization camera. On top of that, the new structure can be made to filter for both color and polarization, allowing for a combination color/polarization camera that measures everything about the light.

Super vision

It is those specific light measurements that provide the unique benefits of this new technology. By measuring the polarization state of a light source, you arrive at a number of interesting applications. One significant capability would be to enhance one’s vision through dust/clouds. When light passes through dust or clouds, it typically is polarized in a certain way. A polarization camera can significantly improve the ability to “see through” these obscurants and more accurately determine one’s target, thus both improving target tracking and reducing targeting errors.

Another important application is biological detection based on chirality, wherein an object does not look the same if you rotate it 180 degrees. With certain biological materials, such as DNA, its helix structure can be used to readily image and identify its chirality characteristics to determine “friend or foe.”

Polarized light can also aid in biological detection, identifying tissue anomalies such as cervical cancer. Polarized light, which focuses its energy in one direction, can enable physicians to better see beneath the surface of the cervix for signs of trouble.

The filter development was funded by the U.S. Air Force Office of Scientific Research (AFOSR).

The United States used to be the most educated society in the world. That's no longer true. (Credit: OECD)

Life in this world is not like it used to be just a few decades ago, and the availability of world-class education on-demand, at almost no cost, is likely to help things change all the more as this century unfolds.

YouTube now hosts more than 500,000 educational videos, on a wide variety of topics. The new mobile-friendly iTunes U also offers 500,000 educational resources and says that 60% of its viewership comes from outside the United States. This global consumption of U.S.-created online educational content may be the newest chapter in a radical transformation of global education over the past 50 years.

During the past 50 years, the expansion of education has contributed to a fundamental transformation of societies in Organization for Economic Co-operation and Development (OECD) countries,” wrote the authors of this year’s lengthy report, Education at a Glance 2011: OECD Indicators. (500 page PDF).

Lake Vostok (credit: NASA)

After drilling for two decades through more than two miles of antarctic ice, Russian scientists are on the verge of entering a vast, dark lake that hasn’t been touched by light for more than 20 million years.

This is the first direct contact with what scientists now know is a web of more than 200 subglacial lakes in Antarctica.

Scientists are enormously excited about what life-forms might be found there but are equally worried about contaminating the lake with drilling fluids and bacteria, and the potentially explosive “de-gassing” of a body of water that has especially high concentrations of oxygen and nitrogen.

 If microbes are found in Vostok, the discovery would have particular significance for astrobiology, because Jupiter’s moon Europa and Saturn’s moon Enceladus have deep ice crusts that scientists think cover large amounts of liquid water warmed by sources other than the sun — just like Vostok.

Age-dependent hypoexcitability of hippocampal CA1 pyramidal neurons (CA1-PCs). Aged mice are shown in gray. (credit: Andrew D. Randall et al./Neurobiology of Aging)

New findings by neuroscientists at the University of Bristol reveal why the brain may become less able to function as we grow older.

In mice studies, the research identified a novel cellular mechanism (sodium channels) underpinning changes to the activity of neurons, which may underlie cognitive decline during normal healthy aging.

The researchers recorded electrical signals in single cells of the hippocampus, a structure with a crucial role in cognitive function to measure “neuronal excitability” — how easy it is to produce brief but very large electrical signals called action potentials (APs).

They found that in the aged brain, it is more difficult to make hippocampal neurons generate action potentials, due to changes to the activation properties of membrane proteins called sodium channels. These mediate the rapid upstroke of the action potential by allowing a flow of sodium ions into neurons.

“Also, by identifying sodium channels as the likely culprit for this reluctance to produce action potentials, our work even points to ways in which we might be able to modify age-related changes to neuronal excitability, and by inference, cognitive ability,” said Professor Randall, University of Bristol Professor in Applied Neurophysiology.

“The mechanism underlying this change in sodium-channel gating properties remains to be explored,” the researchers say.

Ref.: Andrew D. Randall, Clair Booth, Jon T. Brown, Age-related changes to Na+ channel gating contribute to modified intrinsic neuronal excitability, Neurobiology of Aging, 2012; [DOI:10.1016/j.bbr.2011.03.031] (in press)

(Credit: Innovega)

The Defense Advanced Research Projects (DARPA) agency is working with Innovega to create  wearable contact lenses with tiny, full-color displays that digital images can be projected onto to give the wearers better situational awareness in intelligence, surveillance, and reconnaissance (ISR) activities, according to the agency.

iOptiks are contact lenses that enhance normal vision by allowing a wearer to view virtual and augmented reality images without the need for f oversized virtual reality helmets,

Digital images are projected onto tiny full-color displays on the contact lenses. This allows users to focus simultaneously on close-up and far away objects while sill interacting with the surrounding environment.

During the next five years, NASA technology development efforts should focus on 16 high-priority technologies and their associated top technical challenges, says a new report from the National Research Council, sponsored by NASA.

The high-priority technologies include items such as radiation mitigation; guidance, navigation, and control; nuclear systems for both power generation and transportation; and solar power generation.

These priorities were chosen to align with three main facets of NASA’s overall mission: extending and sustaining human activities beyond low Earth orbit; exploring the evolution of the solar system and the potential for life elsewhere; and expanding our understanding of Earth and the universe.

The following table identifies recommended highest-priority technologies for NASA research and development over the next five years:

Objective A

Extend and sustain human activities beyond low Earth orbit

Objective B

Explore the evolution of the solar system and the potential for life elsewhere

Objective C

Expand understanding of Earth and the universe

Radiation Mitigation for Human Spaceflight

Guidance, Navigation, and Control

Optical Systems (Instruments and Sensors)

Long-Duration Crew Health

Solar Power Generation (Photovoltaic and Thermal)

High-Contrast Imaging and Spectroscopy Technologies

Environmental Control and Life Support Systems

Electric Propulsion

Detectors and Focal Planes

Guidance, Navigation, and Control

Fission Power Generation

Lightweight and Multifunctional Materials and Structures

(Nuclear) Thermal Propulsion

Entry, Descent and Landing Thermal Protection Systems

Active Thermal Control of Cryogenic Systems

Lightweight and Multifunctional Materials and Structures

In-Situ Instruments and Sensors

Electric Propulsion

Fission Power Generation

Lightweight and Multifunctional Materials and Structures

Solar Power Generation (Photovoltaic and Thermal)

Entry, Descent, and Landing Thermal Protection Systems

Extreme Terrain Mobility

 

Avatar Polymorph has penned a neat article for H+ Magazine: The Ethics of Boosting Animals from Sentience to Self-Aware Consciousness.On the question of why:What would be the arguments used in favour of such a radical realignment of life, with immortal (by choice) AIs, humans, hybrids and animals?

Secondarily, is it legitimate to use the Homo sapiens, mammalian template as a model for creating self-aware consciousness, culture and language?

In addressing these questions I take the brain as the seat of consciousness, and ignore any religious belief in a ‘soul’.

The first argument is reciprocity. Our example is important in terms of teaching the first AI or AIs while it or they are very briefly children.

If we expect a superintelligent AI to provide us with timely provision of the mechanisms of superintelligence, immortality and perhaps even the theory of everything of physics, then we must have lead by example, even if it is regarding something which we have only been able to support in principle, while lacking the immediate means to achieve it.

We may already possess what might be termed ‘superintelligence of the imagination’ – as a science fiction writer I have read much of this amazing breadth of thought. Amongst my earliest reading material was the famous 1944 novel by Olaf Stapledon, Sirius, concerning a dog whose intelligence was boosted. However, as we can all attest, outside of our imaginations we have limitations of the mundane.

The most everyday languages we can learn is about sixty, the most faces we can remember (an this is one of our key strengths) is about ten thousand. Only about thirty thousand logic trees go into each thought or action.

Even with advanced computational nanomachines embedded in our cerebrospinal fluid – according to TIME magazine, perhaps the equivalent of two hundred thousand human brains – we would still require further superintelligence to make a workable and permanent system quickly. In other words, if we expect to fix ourselves up within a century or less, we will need the assistance of Artificial Intelligence.

The second argument is empathy. While many of us may not feel we have much empathy with a leech, quite a few have empathy with social animals and pets, and indeed love for them.

The third argument is responsibility. If diversity and potential diversity is a positive feature of mortal life, one we now look for in our children as reflections of ourselves, then it should be reflected in immortal life.

Unlike Peter Singer, the popularizer of Animal Liberation, I believe that continuity is important. That a human baby is no different from a dog for some months is no grounds to ignore its future state. Similarly, with the potential abilities of the near future, we could regard a dog as a gestating ‘super-dog’.

The fourth argument is that it is fun to have more immortal beings around, with which we can interact.

The fifth argument is that it is fun to have more kids to raise.

The sixth argument is that under future conditions such as full automation, distributed production, individuated design, robotics, 3D printers and eventually nanotechnological assemblers (a much more advanced form of 3D printers, also known as nanofactories or molecular manufacturing) it will not cost us anything.

While I am not advocating megascale solar sytem engineering I also note that 1990s estimates of the maximum number of beings capable of being supported by all the material of the solar system as about 600 billion and certainly there is a lot of scope for all the current inhabitants of the planetary biosphere.

The seventh and final argument is that by making a current adult human the minimum requirement for a neural map for a birthed consciousness (along with the normal developmental period of adolescence) we have a reasonable sliding scale that involves no moral guilt for failed help.

Anders Sandberg and Stuart Armstrong are currently putting together a paper explaining why the presence of Dyson Spheres would actually deepen the mystery that is the Fermi Paradox. Armstrong recently gave a talk on the subject, titled "von Neumann probes, Dyson spheres, exploratory engineering and the Fermi paradox."


Sandberg writes:It is based on a paper we are writing together that analyses how much harder the Fermi question (because it is not really a paradox, just a question with answers we tend to dislike/disagree on) becomes once you take modern ideas about self replication and exploratory engineering into account. The main finding is that intergalactic expansion is likely doable using local resources and a very high branching factor, and that makes the solar neighbourhood accessible to at least millions of times more potential alien civilizations. So either alien civilizations have to be even rarer than we think, they have to approach some non-visible behavioural attractor with very high fidelity, or they are here and hiding efficiently (in this case likely because the first expanding civilization used its probes to enforce some set of rules for everybody else).

My friend and colleague Stuart Armstrong gave a talk titled von Neumann probes, Dyson spheres, exploratory engineering and the Fermi paradox to the physics department yesterday. It is based on a paper we are writing together that analyses how much... Anders3 http://www.aleph.se/ asa@nada.kth.se

A great magnetic bubble surrounds the solar system as it cruises through the galaxy. The sun pumps the inside of the bubble full of solar particles that stream out to the edge until they collide with the material that fills the rest of the galaxy, at a complex boundary called the heliosheath. On the other side of the boundary, electrically charged particles from the galactic wind blow by, but rebound off the heliosheath, never to enter the solar system. Neutral particles, on the other hand, are a different story. They saunter across the boundary as if it weren't there, continuing on another 7.5 billion miles for 30 years until they get caught by the sun's gravity, and sling shot around the star. There, NASA's Interstellar Boundary Explorer lies in wait for them ... (Credit: NASA)

NASA’s Interstellar Boundary Explorer (IBEX) has captured the best and most complete glimpse yet of what lies beyond the solar system.

The new measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and the history of other stars in the Milky Way.

The Earth-orbiting spacecraft observed four separate types of atoms including hydrogen, oxygen, neon and helium. These interstellar atoms are the byproducts of older stars, which spread across the galaxy and fill the vast space between stars.

IBEX determined the distribution of these elements outside the solar system, which are flowing charged and neutral particles that blow through the galaxy, or the so-called interstellar wind.

In a series of science papers appearing in the Astrophysics Journal on Jan. 31, scientists report finding 74 oxygen atoms for every 20 neon atoms in the interstellar wind. In our own solar system, there are 111 oxygen atoms for every 20 neon atoms. This translates to more oxygen in any part of the solar system than in nearby interstellar space.

NASA's Interstellar Boundary Explorer (IBEX) studies the outer boundaries of the solar system, where particles from the solar wind collide with particles from the galactic wind (credit: NASA)

“Our solar system is different than the space right outside it, suggesting two possibilities,” says David McComas, IBEX principal investigator, at the Southwest Research Institute in San Antonio.

“Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside, or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space.”

The new results hold clues about the history of material in the universe. While the big bang initially created hydrogen and helium, only the supernovae explosions at the end of a star’s life can spread the heavier elements of oxygen and neon through the galaxy. Knowing the amounts of elements in space may help scientists map how our galaxy evolved and changed over time.

Exploring the interstellar medium

Scientists want to understand the composition of the boundary region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere. The heliosphere acts as a protective bubble that shields our solar system from most of the dangerous galactic cosmic radiation that otherwise would enter the solar system from interstellar space.

IBEX measured the interstellar wind traveling at a slower speed than previously measured by the Ulysses spacecraft, and from a different direction. The improved measurements from IBEX show a 20 percent difference in how much pressure the interstellar wind exerts on our heliosphere.

“Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there will help determine the size and shape of our solar system as it travels through the galaxy,” says Eric Christian, IBEX mission scientist, at NASA’s Goddard Space Flight Center in Greenbelt, Md.

The IBEX spacecraft was launched in October 2008. Its science objective is to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system.

The galactic wind streams toward the sun from the direction of Scorpio and IBEX has found that it travels at 52,000 miles an hour. The speed of the galactic wind and its subsequent pressure on the outside of the solar system's boundary affects the shape of the heliosphere as it travels through space (credit: NASA/Goddard Scientific Visualization Studio)

The Southwest Research Institute developed and leads the IBEX mission with a team of national and international partners.

The spacecraft is one of NASA’s series of low-cost, rapidly developed missions in the Small Explorers Program. Goddard manages the program for the agency’s Science Mission Directorate at NASA Headquarters in Washington.

Among the six U.S. institutions on the IBEX mission are the University of New Hampshire (UNH), the LMATC, SwRI, the University of Texas, San Antonio, MIT, and the University of Chicago.

See also:

February issue of The Astrophysical Journal Supplement Series (written by IBEX team members)
IBEX: Glimpses of the Interstellar Material Beyond our Solar System (NASA)
IBEX Team, UNH Scientist Present Mission Findings Today at NASA Press Conference (UNH)

A survey of entrepreneurs found that most started their first company at age 39. People with degrees in computer science started companies much sooner than those with advanced training in other sciences or engineering. (Credit: Kauffman Foundation)

Research by Vivek Wadhwa, VP of academics and innovation at Singularity University, and his team found in a survey that the average and median age of the founders of successful U.S. technology businesses (with real revenues) is 39.

They found twice as many successful founders over 50 as under 25, and twice as many over 60 as under 20.

However, “understanding diverse technologies isn’t the domain of the young,” Wadhwa says.

“Though college dropouts may know all about social media, it is very unlikely that they understand the intricacies of nanotechnology and artificial intelligence as well as their elders do. These are complex technologies that require not only a strong education but also the ability to work across domains and collaborate with intellectual peers in different disciplines of science and engineering.”

Neural precursor cells (upper left) differentiate into oligodendrocytes, astrocytes, and neurons (credit: Ernesto Lujana et al./PNAS)

Mouse skin cells can be converted directly into cells that become the three main parts of the nervous system, according to researchers at the Stanford University School of Medicine.

The finding is an extension of a previous study by the same group showing that mouse and human skin cells can be directly converted into functional neurons.

Neural precursor cells

This new study transforms the skin cells into neural precursor cells, as opposed to just neurons. They can also become the two other main cell types in the nervous system: astrocytes and oligodendrocytes.

Neural precursor cells offer another advantage over neurons:they can be cultivated to large numbers in the laboratory — a feature critical for their long-term usefulness in transplantation or drug screening. The finding implies that it may one day be possible to generate a variety of neural-system cells for transplantation that would perfectly match a human patient.

“We’ve shown the cells can integrate into a mouse brain and produce a missing protein important for the conduction of electrical signal by the neurons,” said Marius Wernig, MD, assistant professor of pathology and a member of Stanford’s Institute for Stem Cell Biology and Regenerative Medicine. “This is important because the mouse model we used mimics that of a human genetic brain disease. However, more work needs to be done to generate similar cells from human skin cells and assess their safety and efficacy.”

Bypassing induced pluripotency and embryonic stem cells

The multiple successes of the direct conversion method could refute the idea that pluripotency (a term that describes the ability of stem cells to become nearly any cell in the body) is necessary for a cell to transform from one cell type to another. Together, the results raise the possibility that embryonic stem cell research and another technique called “induced pluripotency” could be supplanted by a more direct way of generating specific types of cells for therapy or research.

Scientists had thought that it was necessary for a cell to first enter an induced pluripotent state or for researchers to start with an embryonic stem cell, which is pluripotent by nature, before it could go on to become a new cell type. However, research from Wernig’s laboratory in early 2010 showed that it was possible to directly convert one “adult” cell type to another with the application of specialized transcription factors, a process known as transdifferentiation.

“Dr. Wernig’s demonstration that fibroblasts can be converted into functional nerve cells opens the door to consider new ways to regenerate damaged neurons using cells surrounding the area of injury,” said pediatric cardiologist Deepak Srivastava, MD, who was not involved in these studies.

“It also suggests that we may be able to transdifferentiate cells into other cell types.” Srivastava is the director of cardiovascular research at the Gladstone Institutes at the University of California-San Francisco. In 2010, Srivastava transdifferentiated mouse heart fibroblasts into beating heart muscle cells.

“Direct conversion [from skin] has a number of advantages,” said Graduate student Ernesto Lujan, the first author. “It occurs with relatively high efficiency and it generates a fairly homogenous population of cells. In contrast, cells derived from iPS cells must be carefully screened to eliminate any remaining pluripotent cells or cells that can differentiate into different lineages.” Pluripotent cells can also cause cancers when transplanted into animals or humans, according to the scientists.

Human transplantation experiments

The scientists are now working to replicate the work with skin cells from adult mice and humans, but Lujan emphasized that much more research is needed before any human transplantation experiments could be conducted. In the meantime, however, the ability to quickly and efficiently generate neural precursor cells that can be grown in the laboratory to mass quantities and maintained over time will be valuable in disease and drug-targeting studies.

“In addition to direct therapeutic application, these cells may be very useful to study human diseases in a laboratory dish or even following transplantation into a developing rodent brain,” said Wernig.

Ref.: E. Lujan, et al., Direct conversion of mouse fibroblasts to self-renewing, tripotent neural precursor cells, Proceedings of the National Academy of Sciences, 2012; [DOI:10.1073/pnas.1121003109]

“We’re all cyborgs now,” the anthropologist Amber Case said in a TED talk in 2010.

Our devices allow us to compress time and space in a way that we’re able to mentally transport ourselves between planes of existence with the touch of a button. (Or, rather, a digital rendering of a button.)

This is the dilemma of being a cyborg: it’s that we’re collectively engaged in a mass conversion of what we used to call, variously, records, accounts, entries, archives, registers, collections, keepsakes, catalogs, testimonies and memories into, simply, data.

We’ve outsourced our memories to external devices, said science journalist Joshua Foer. “The result is that we no longer trust our memories. We see every small, forgotten thing as evidence that they’re failing us altogether.” As we store more and more of what makes us us outside of ourselves, “we’ve forgotten how to remember.”

(Credit: James Duncan Davidson/TED)

TED will host auditions in 14 countries on six continents this spring, reports the Mashable blog. Anybody can submit an application on the TED website, and include a short video if they’d like, but auditions are invite-only.

Favorites from live auditions will record short videos to post on TED.com for public voting, and the top 50 most popular contenders will be considered for TED 2013 programming.

TED’s website says the organization is looking for “undiscovered talent,” perhaps “the inventor,” “the teacher,” “the prodigy” or “the artist.” It is not looking for “product-hawkers, jargon-junkies, dullards, wafflers, motivator wannabes, self-promoters, spouters of new-age fluff.”

Britain is one step closer to conducting the first clinical tests of reproductive techniques that combine parents’ genes with DNA from a third party. The approach could spare children from inheriting some rare diseases, including forms of muscular dystrophy and neurodegenerative disorders that affect around 1 in 5,000 people. From Nature:These conditions are caused by defects in the mitochondria, the ‘power packs’ of the cell, which are inherited from a child’s mother through the egg. Experiments on primates, and with defective human eggs, have already shown that genetic material can be removed from an egg that has faulty mitochondria and transferred to a healthy donor ovum, leaving the flawed mitochondrial DNA behind. In principle, the resulting egg could then develop into a healthy child carrying both the parents’ nuclear genes and mitochondrial DNA from the donor. But the work amounts to genetic modification of embryos — which is currently illegal in the United Kingdom — and also involves destroying fertilized eggs.

On 19 January, the UK government’s Human Fertilisation and Embryology Authority (HFEA) announced a public consultation on the process, the first step towards making it legal. Simultaneously, the country’s biggest biomedical charity, the Wellcome Trust, said that it would fund preclinical experiments to gauge the safety of the techniques. An independent bioethical review is also in progress. “It’s a wonderful example of how regulation should work, because it’s saying let’s see the science, let’s see the bioethics, let’s find out what the public thinks,” says Peter Braude, a reproductive biologist at King’s College London.More.

Fred Trotter, in his article, AI will eventually drive healthcare, but not anytime soon, says that the merging of artificial intelligence and healthcare is tougher than many realize. On the search space problem he writes:Any person even reasonably informed about AI knows about Go, an ancient game with simple rules. Those simple rules hide the fact that Go is a very complex game indeed. For a computer, it is much harder to play than chess.

Almost since the dawn of computing, chess was regarded as something that required intelligence and was therefore a good test of AI. In 1997, the world chess champion was beaten by a computer. In the year after, a professional Go player beat the best Go software in the world with a 25 stone handicap. Artificial intelligence experts study Go carefully precisely because it is so hard for computers. The approach that computers take toward being smart — thinking of lots of options really fast — stops working when the number of options skyrockets, and the number of potentially right answers also becomes enormous. Most significantly, Go can always be made more computationally difficult by simply expanding the board.

Make no mistake, the diagnosis and treatment of human illness is like Go. It's not like chess. Khosla is making a classic AI mistake, presuming that because he can discern the rules easily, it means the game is simple. Chess has far more complex rules than Go, but it ends up being a simpler game for computers to play.

To be great at Go, software must learn to ignore possibilities, rather than searching through them. In short, it must develop "Go instincts." The same is true for any software that could claim to be a diagnostician.

How can you tell when software diagnosticians are having search problems? When they cannot tell the difference between all of the "right" answers to a particular problem. The average doctor does not need to be told "could it be Zebra Fever?" by a computer that cannot tell that it should have ignored any zebra-related possibilities because it is not physically located in Africa. (No zebras were harmed in the writing of this article, and I do not believe there is a real disease called Zebra Fever.)Trotter also discusses what he calls the good data problem. Read more here.

An X-ray CT scan of the head of one of the volunteers, showing electrodes distributed over the brain’s temporal lobe, where sounds are processed. (Credit: Adeen Flinker, UC Berkeley)

Neuroscientists may one day be able to hear the imagined speech of a patient unable to speak due to stroke or paralysis, according to University of California, Berkeley researchers.

These scientists have succeeded in decoding electrical activity in the brain’s temporal lobe — the seat of the auditory system — as a person listens to normal conversation. Based on this correlation between sound and brain activity, they then were able to predict the words the person had heard solely from the temporal lobe activity.

Audio file for original and reconstructed words

“This is huge for patients who have damage to their speech mechanisms because of a stroke or Lou Gehrig’s disease and can’t speak,” said co-author Robert Knight, a UC Berkeley professor of psychology and neuroscience. “If you could eventually reconstruct imagined conversations from brain activity, thousands of people could benefit.”

“This research is based on sounds a person actually hears, but to use it for reconstructing imagined conversations, these principles would have to apply to someone’s internal verbalizations,” cautioned first author Brian N. Pasley, a post-doctoral researcher in the center.

“There is some evidence that hearing the sound and imagining the sound activate similar areas of the brain. If you can understand the relationship well enough between the brain recordings and sound, you could either synthesize the actual sound a person is thinking, or just write out the words with a type of interface device.”

Subjects listened to words (acoustic waveform, top left) while neural signals were recorded from cortical surface electrode arrays (top right, red circles) implanted over superior and middle temporal gyrus (STG, MTG). Speech-induced cortical field potentials (bottom right, gray curves) recorded at multiple electrode sites were used to fit multi-input, multi-output models for offline decoding. The models take as input time-varying neural signals at multiple electrodes and output a spectrogram consisting of time-varying spectral power across a range of acoustic frequencies (180-7000 Hz, bottom left). To assess decoding accuracy, the reconstructed spectrogram is compared to the spectrogram of the original acoustic waveform. (Credit: Brian N. Pasley)

In addition to the potential for expanding the communication ability of the severely disabled, he noted, the research also “is telling us a lot about how the brain in normal people represents and processes speech sounds.”

They enlisted the help of people undergoing brain surgery to determine the location of intractable seizures so that the area can be removed in a second surgery. Neurosurgeons typically cut a hole in the skull and safely place electrodes on the brain surface or cortex — in this case, up to 256 electrodes covering the temporal lobe — to record activity over a period of a week to pinpoint the seizures. For this study, 15 neurosurgical patients volunteered to participate.

Pasley visited each person in the hospital to record the brain activity detected by the electrodes as they heard 5 to 10 minutes of conversation. Pasley used this data to reconstruct and play back the sounds the patients heard. He was able to do this because there is evidence that the brain breaks down sound into its component acoustic frequencies — for example, between a low of about 1 Hz (cycles per second) to a high of about 8,000 Hz — that are important for speech sounds.

.

Spectrograms of the original and reconstructed words. For audio playback, the spectrogram or modulation representations must be converted to an acoustic waveform, a transformation that requires both magnitude and phase information. Because the reconstructed representations are magnitude-only, the phase must be estimated. (Credit: Brian N. Pasley)

Audio file for original and reconstructed words

Pasley tested two different computational models to match spoken sounds to the pattern of activity in the electrodes. The patients then heard a single word, and Pasley used the models to predict the word based on electrode recordings.

“We are looking at which cortical sites are increasing activity at particular acoustic frequencies, and from that, we map back to the sound,” Pasley said. He compared the technique to a pianist who knows the sounds of the keys so well that she can look at the keys another pianist is playing in a sound-proof room and “hear” the music, much as Ludwig van Beethoven was able to “hear” his compositions despite being deaf.

The better of the two methods was able to reproduce a sound close enough to the original word for Pasley and his fellow researchers to correctly guess the word.

“We think we would be more accurate with an hour of listening and recording and then repeating the word many times,” Pasley said. But because any realistic device would need to accurately identify words heard the first time, he decided to test the models using only a single trial.

“This research is a major step toward understanding what features of speech are represented in the human brain” Knight said. “Brian’s analysis can reproduce the sound the patient heard, and you can actually recognize the word, although not at a perfect level.”

Knight predicts that this success can be extended to imagined, internal verbalizations, because scientific studies have shown that when people are asked to imagine speaking a word, similar brain regions are activated as when the person actually utters the word.

“With neuroprosthetics, people have shown that it’s possible to control movement with brain activity,” Knight said. “But that work, while not easy, is relatively simple compared to reconstructing language. This experiment takes that earlier work to a whole new level.”

The current research builds on work by other researchers about how animals encode sounds in the brain’s auditory cortex. In fact, some researchers, including the study’s coauthors at the University of Maryland, have been able to guess the words ferrets were read by scientists based on recordings from the brain, even though the ferrets were unable to understand the words.

The ultimate goal of the UC Berkeley study was to explore how the human brain encodes speech and determine which aspects of speech are most important for understanding.

“At some point, the brain has to extract away all that auditory information and just map it onto a word, since we can understand speech and words regardless of how they sound,” Pasley said. “The big question is, What is the most meaningful unit of speech? A syllable, a phone, a phoneme? We can test these hypotheses using the data we get from these recordings.”

Chang and Knight are members of the Center for Neural Engineering and Prostheses, a joint UC Berkeley/UCSF group focused on using brain activity to develop neural prostheses for motor and speech disorders in disabling neurological disorders.

Ref.: Brian N. Pasley et al., Reconstructing speech from human auditory cortex, PLoS Biology, Jan. 31, 2012 [link]

The structural DNA path toward productive nanosystems has achieved another step forward with the demonstration that a DNA origami scaffolding can be used to program a DNA motor to navigate a network of tracks. A hat tip to PhysOrg.com for reprinting this news release from Kyoto University “DNA Motor Programmed to Navigate a Network of Tracks“:

Kyoto, Japan — Expanding on previous work with engines traveling on straight tracks, a team of researchers at Kyoto University and the University of Oxford have successfully used DNA building blocks to construct a motor capable of navigating a programmable network of tracks with multiple switches. The findings, published in the January 22 online edition of the journal Nature Nanotechnology [abstract], are expected to lead to further developments in the field of nanoengineering.

The research utilizes the technology of DNA origami, where strands of DNA molecules are sequenced in a way that will cause them to self-assemble into desired 2D and even 3D structures. In this latest effort, the scientists built a network of tracks and switches atop DNA origami tiles, which made it possible for motor molecules to travel along these rail systems.

“We have demonstrated that it is not only possible to build nanoscale devices that function autonomously,” explained Dr. Masayuki Endo of Kyoto University’s Institute for Integrated Cell-Material Sciences (iCeMS), “but that we can cause such devices to produce predictable outputs based on different, controllable starting conditions.”

The team, including lead author Dr. Shelley Wickham at Oxford, expects that the work may lead to the development of even more complex systems, such as programmable molecular assembly lines and sophisticated sensors.

“We are really still at an early stage in designing DNA origami-based engineering systems,” elaborated iCeMS Prof. Hiroshi Sugiyama. “The promise is great, but at the same time there are still many technical hurdles to overcome in order to improve the quality of the output. This is just the beginning for this new and exciting field.”

Courtesy Sugiyama Lab, Kyoto University iCeMS

A depiction of a DNA origami tile with a built-in network of tracks. The DNA engine or motor, in red, can be programmed to navigate a series of junctions to reach one of four desired end points.

Perhaps the next step is to have multiple addressable DNA motors bring different components together to be joined?
—James Lewis

Experimental phase change memory chip (credit: Samsung)

Researchers at IBM and elsewhere are exploring the idea that phase change materials (PCMs) could hold more information by switching between an amorphous state and a crystalline one.

PCM memory can write and retrieve data 100 times faster than Flash memory, which is used in many consumer gadgets and computers. It is also extremely durable and can be reused at least 10 million times; Flash can cope with just 3000 uses.

But PCM memory’s true potential lies in its ability to store more than a single bit per cell. “If you are able to control the current you can create states between the two, something that is not fully crystallized and something that is not fully amorphous,” says Evangelos Eleftheriou, head of storage technologies at IBM’s Zurich Research Laboratory in Switzerland.

Precisely how many states can be created remains to be seen, but some researchers, like David Wright at the University of Exeter in the UK, have already demonstrated 512 discrete states in a single 20-nanometre cell — about the same size as a Flash memory cell, which usually only holds two.