27 October 2016

360 Degree Electronic Holographic Display

Researchers described a novel tabletop display system that allows multiple viewers to simultaneously view a hologram showing a full 3D image as they walk around the tabletop, giving complete 360-degree access. To be commercially feasible in a range of applications -- from medicine to gaming to media -- the hologram challenge is daunting. It involves scaling an electronic device to a size small enough to fit on a table top, while making it robust enough to render immense amounts of data needed to create a full-surround 3D viewing experience from every angle -- without the need for special glasses or other viewing aids. In the past, researchers interested in holographic display systems proposed or focused on methods for overcoming limitations in the combined spatial resolution and speed of commercially available, spatial light modulators. Representative techniques included space-division multiplexing (SDM), time-division multiplexing (TDM) and combination of those two techniques. Researchers from the 5G Giga Communication Research Laboratory, Electronics and Telecommunications Research Institute, South Korea took a different approach. They devised and added a novel viewing window design.

To implement such a viewing window design, close attention had to be paid to the optical image system. With a tabletop display, a viewing window can be created by using a magnified virtual hologram, but the plane of the image is tilted with respect to the rotational axis and is projected using with two parabolic mirrors. "But because the parabolic mirrors do not have an optically-flat surface, visual distortion can result. We needed to solve the visual distortion by designing an aspheric lens. As a result, multiple viewers are able to observe 3.2-inch size holograms from any position around the table without visual distortion. Building on these advances, the team hopes to implement a key design feature of strategically sizing the viewing window so it is closely related to the effective pixel size of the rotating image of the virtual hologram. Watching through this window, observers' eyes are positioned to accept the holographic image light field because the system tilts the virtual hologram plane relative to the rotational axis. To enhance the viewing experience the team hopes to design a system in which observers can see 3.2-inch holographic 3D images floating on the surface of the parabolic mirror system at a rate of 20 frames per second. Test results of the system using a 3D model and computer-generated holograms were promising.

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26 October 2016

Brain Surface Stimulation Provides Touch Feedback

For the first time in humans, researchers use brain surface stimulation to provide 'touch' feedback to direct movement. In the quest to restore movement to people with spinal cord injuries, researchers have focused on getting brain signals to disconnected nerves and muscles that no longer receive messages that would spur them to move. But grasping a cup or brushing hair or cooking a meal requires other feedback that has been lost in amputees and individuals with paralysis -- a sense of touch. The brain needs information from a fingertip or limb or external device to understand how firmly a person is gripping or how much pressure is needed to perform everyday tasks.

Now, University of Washington researchers at the National Science Foundation Center for Sensorimotor Neural Engineering (CSNE) have used direct stimulation of the human brain surface to provide basic sensory feedback through artificial electrical signals, enabling a patient to control movement while performing a simple task: opening and closing his hand. It's a first step towards developing "closed loop," bi-directional brain-computer interfaces (BBCIs) that enable two-way communication between parts of the nervous system. They would also allow the brain to directly control external prosthetics or other devices that can enhance movement while getting sensory feedback.

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24 October 2016

Happiness Makes us Less Creative

Corporations intent on making employees more engaged and creative are focusing on happiness as the answer. Chief Happiness Officer is an actual job at many companies. But most scientists say that creativity calls on persistence and problem-solving skills, not positivity. Researchers at Kent University and Sussex University in England dug through through over half century of study on the creative process in various fields, and isolated 14 components of creativity. Happiness wasn’t one of them. Creativity is complex. The 14 components they found all need to work together to varying degrees depending on the task at hand, the researchers explain. None is more important than any other although different creative activities (and different steps of a single creative effort) may demand more of one or another and build on each other.

Psychologists at the University of North Texas Department of Management divided creativity into two phases; initial idea generation and subsequent problem-solving. Their review of research on feelings and creativity concluded that a positive mood is useful when first brainstorming, processing information, and coming up with as many ideas as possible—you don’t want to bring judgment into that, because it could stifle idea generation. But rigor is the key to overcoming obstacles and completing tasks—and good mood doesn’t improve problem-solving, which involves judgments that almost by necessity won’t feel good: critique and evaluation, experimentation and failure. The stress that arises from problems may be unpleasant but it also motivates us to complete tasks. In other words, negative emotions are actually beneficial to the creative process.

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22 October 2016

Doctors Much Bettter Than Computers

Increasingly powerful computers using ever-more sophisticated programs are challenging human supremacy in areas as diverse as playing chess and making emotionally compelling music. But can digital diagnosticians match, or even outperform, human physicians? The answer, according to a new study led by researchers at Harvard Medical School, is not quite. The findings, show that physicians' performance is vastly superior and that doctors make a correct diagnosis more than twice as often as 23 commonly used symptom-checker apps. The analysis is believed to provide the first direct comparison between human-made and computer-based diagnoses. Diagnostic errors stem from failure to recognize a disease or to do so in a timely manner. Physicians make such errors roughly 10 to 15 percent of the time, researchers say. Over the last two decades, computer-based checklists and other fail-safe digital apps have been increasingly used to reduce medication errors or streamline infection-prevention protocols.

Each year, hundreds of millions of people use Internet programs or apps to check their symptoms or to self-diagnose. Yet how these computerized symptom-checkers fare against physicians has not been well studied. In the study, 234 internal medicine physicians were asked to evaluate 45 clinical cases, involving both common and uncommon conditions with varying degrees of severity. For each scenario, physicians had to identify the most likely diagnosis along with two additional possible diagnoses. Each clinical vignette was solved by at least 20 physicians. The physicians outperformed the symptom-checker apps, listing the correct diagnosis first 72 percent of the time, compared with 34 percent of the time for the digital platforms. Eighty-four percent of clinicians listed the correct diagnosis in the top three possibilities, compared with 51 percent for the digital symptom-checkers. The difference between physician and computer performance was most dramatic in more severe and less common conditions. It was smaller for less acute and more common illnesses.

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17 October 2016

Adaptive Brain

Human babies and even animals have a basic number sense that many believe evolves from seeing the world and trying to quantify all the sights. But vision has nothing to do with it -- Johns Hopkins University neuroscientists have found that the brain network behind numerical reasoning is identical in blind and sighted people. The researchers also found the visual cortex in blind people is highly involved in doing math, suggesting the brain is vastly more adaptable than previously believed. The findings are published online in the journal Proceedings of the National Academy of Sciences. The researchers had congenitally blind people and sighted people wearing blindfolds solve math equations and answer language questions while having a brain scan. With the math problems, participants heard pairs of increasingly complicated recorded equations and responded if the value for "x" was the same or different.

The participants also heard pairs of sentences and responded if the meaning of the sentences was the same or different. With both blind and sighted participants, the key brain network involved in numerical reasoning, the intraparietal sulcus, responded robustly as participants considered the math problems. Meanwhile, in blind participants only, regions of the visual cortex also responded as they did math. And the visual cortex didn't merely respond -- the more complicated the math, the greater the activity in the vision center. Although it had been thought that brain regions including the visual cortex had entrenched functions that could change slightly but not fundamentally, these findings underscore recent research that showed just the opposite: The visual cortex is extremely plastic and, when it isn't processing sight, can respond to everything from spoken language to math problems.

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16 October 2016

The Secrets of the Learning Brain

Something must change in our brain to store the information, and how it does so, remains a mystery. Researchers investigated what happens, at the smallest scales, in a single one of the quadrillion (a million times a billion) connections in our brain. By modeling the biophysical processes that take place there, they discovered that the shape of the connections plays a crucial role in regulating their strength. The brain contains billions of interconnected nerve cells. On each of the ‘tentacles’ of these cells, tiny ‘microspines’ reach out to the tentacles of other nerve cells. The point at which they are closest together is called the synapse. At the synapse, the sending nerve cell converts electrical signals into chemical signals, which are picked up at the receiving nerve cell and converted back into an electrical signal so that it may continue its journey. Precisely how this signal transmission is regulated at the synapse is key to our ability to learn and remember. Using models and computer simulations, researchers examined the physical processes that happen on, and in, the microspine.

As it turns out, that this particular shape is important – and remarkably effective – in regulating the strength of the connection. For this strength, the number of receptors that are around to relay the signal is crucial. These receptors must, of course, come from somewhere. They are transported in small membrane containers that have to pass through the neck of the mushroom. If it is too narrow, the supply comes to a halt, weakening the strength of the brain connection. So it would appear that the neck of the mushroom is hindering strong connections. Kusters discovered, however, that there is a different side to this story. The receptors are small proteins that are able to move around, exploring the surface of the mushroom. This means that they may spontaneously escape. Narrow necks, it turns out, make it much more difficult for the receptors to drift away. The narrow neck also serves to keep receptors already on the mushroom around for longer. So, the shape of the mushroom controls the balance between supply and loss of receptors, and thereby the strength of the neuronal connection.

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09 October 2016

Researchers Night 2016

On the 30th of September 2016, there was the demonstration of ‘European Researchers' Night: exploring science whilst having fun’. There were a number of visitors, experiencing novel research methods in different areas.

The HCI Lab has presented a number of interesting demos, covering areas of immersive virtual reality, serious games, visualization and human-computer interaction.  More than 200 people have experienced our demos.

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