SpaceCollective: gamma

SpaceCollective: gamma http://spacecollective.org/gamma Wed, 15 May 2013 08:27:08 +0000 http://spacecollective.org/gamma en Chaos in sync - new communication systems http://spacecollective.org/gamma/8607/Chaos-in-sync-new-communication-systems http://spacecollective.org/gamma/8607/Chaos-in-sync-new-communication-systems Wed, 15 May 2013 08:27:08 +0000 gamma 8607 <img src="http://spacecollective.org/userdata/GH93ehia/1368631798/strange attractor in oscilloscope.png" border="0" width="" height="" align="left" class="padRight"> (Phys.org) —In today's wireless communication systems, the wireless signals are non-chaotic, meaning they have a well-defined period and frequency. Non-chaotic wireless signals are used in many applications, such as satellite communications, GPS navigation, cell phones, and Wi-Fi devices. However, as many people know first-hand, wireless systems usually have inferior performance compared to wired systems. The problem is due to physical impediments that the wireless signal faces in open space caused by the atmosphere, water, mountains, buildings, and other different media. Now in a new study, researchers have investigated how wireless communication could be implemented with chaotic signals, and found that chaotic signals could overcome some of these physical constraints and lead to superior performance... <a href="http://phys.org/news/2013-05-chaos-wireless.html" target="blank">http://phys.org/news/2013-05-chaos-wireless.html</a> <a href="http://prl.aps.org/pdf/PRL/v110/i18/e184101" target="blank">http://prl.aps.org/pdf/PRL/v110/i18/e184101</a> <a href="http://en.wikipedia.org/wiki/Lorenz_system" target="blank">http://en.wikipedia.org/wiki/Lorenz_system</a> <a href="http://en.wikipedia.org/wiki/Lyapunov_exponent" target="blank">http://en.wikipedia.org/wiki/Lyapunov_exponent</a> <a href="http://en.wikipedia.org/wiki/Topological_entropy" target="blank">http://en.wikipedia.org/wiki/Topological_entropy</a> "Traditionally, engineers sought to minimize noise and distortion in system designs. Today, Aerospace scientists are seeking to explicitly harness these effects for useful engineering purposes..." <a href="http://www.aerospace.org/publications/crosslink-magazine/crosslink-spring-2011/nonlinear-dynamics-and-chaos-from-concept-to-application/" target="blank">http://www.aerospace.org/publications/crosslink-magazine/crosslink-spring-2011/nonlinear-dynamics-and-chaos-from-concept-to-application/</a>  <a href="http://fourier.eng.hmc.edu/e84/silva.pdf" target="blank">http://fourier.eng.hmc.edu/e84/silva.pdf</a>  http://spacecollective.org/gamma/8607/Chaos-in-sync-new-communication-systems Another recording of a dream http://spacecollective.org/gamma/8345/Another-recording-of-a-dream http://spacecollective.org/gamma/8345/Another-recording-of-a-dream Wed, 24 Apr 2013 03:24:40 +0000 gamma 8345 Reconstructing Visual Experiences from Brain Activity Evoked by Natural Movies Quantitative modeling of human brain activity can provide crucial insights about cortical representations [1 and 2] and can form the basis for brain decoding devices [3, 4 and 5]. Recent functional magnetic resonance imaging (fMRI) studies have modeled brain activity elicited by static visual patterns and have reconstructed these patterns from brain activity [6, 7 and 8]. However, blood oxygen level-dependent (BOLD) signals measured via fMRI are very slow [9], so it has been difficult to model brain activity elicited by dynamic stimuli such as natural movies. Here we present a new motion-energy [10 and 11] encoding model that largely overcomes this limitation. The model describes fast visual information and slow hemodynamics by separate components. We recorded BOLD signals in occipitotemporal visual cortex of human subjects who watched natural movies and fit the model separately to individual voxels. Visualization of the fit models reveals how early visual areas represent the information in movies. To demonstrate the power of our approach, we also constructed a Bayesian decoder [8] by combining estimated encoding models with a sampled natural movie prior. The decoder provides remarkable reconstructions of the viewed movies. These results demonstrate that dynamic brain activity measured under naturalistic conditions can be decoded using current fMRI technology.  <a href="http://www.sciencedirect.com/science/article/pii/S0960982211009377" target="blank">http://www.sciencedirect.com/science/article/pii/S0960982211009377</a>  http://spacecollective.org/gamma/8345/Another-recording-of-a-dream The know-how of non-photonic communication http://spacecollective.org/gamma/8339/The-knowhow-of-nonphotonic-communication http://spacecollective.org/gamma/8339/The-knowhow-of-nonphotonic-communication Thu, 18 Apr 2013 14:15:38 +0000 gamma 8339 "Alice and Bob communicate without transferring a single photon" <img src="http://spacecollective.org/userdata/GH93ehia/1366319719/PW-2013-04-163-Communication-without-particles-pic2[1].jpg" border="0" width="" height="" class="padTopBot">  <a href="http://physicsworld.com/cws/article/news/2013/apr/16/alice-and-bob-communicate-without-transferring-a-single-photon" target="blank">http://physicsworld.com/cws/article/news/2013/apr/16/alice-and-bob-communicate-without-transferring-a-single-photon</a>  http://spacecollective.org/gamma/8339/The-knowhow-of-nonphotonic-communication OpenBadge technology for skill recognition http://spacecollective.org/gamma/8318/OpenBadge-technology-for-skill-recognition http://spacecollective.org/gamma/8318/OpenBadge-technology-for-skill-recognition Tue, 19 Mar 2013 15:34:40 +0000 gamma 8318 <div align="center"><img src="http://spacecollective.org/userdata/GH93ehia/1363732581/310304_549539035068581_993410430_n[1].png" width="" height="" border="0" /></div> Get recognition for skills you learn anywhere. Earn badges for skills you learn online and offline Issue Give recognition for things you teach Show your badges in the places that matter Introducing Open Badges - a new online standard to recognize and verify learning:  <a href="http://openbadges.org/" target="blank">http://openbadges.org/</a>  http://spacecollective.org/gamma/8318/OpenBadge-technology-for-skill-recognition Telepathy by cable http://spacecollective.org/gamma/8310/Telepathy-by-cable http://spacecollective.org/gamma/8310/Telepathy-by-cable Sat, 02 Mar 2013 08:21:30 +0000 gamma 8310 <img src="http://spacecollective.org/userdata/GH93ehia/1362241826/Telepathic-rats[1].jpg" border="0" width="" height="" class="padTopBot"> Mind-reading rodents: Scientists show 'telepathic' rats can communicate using brain-to-brain Scientists also claim wires connecting one rodent to another can allow communication spanning continents via the internet  <a href="http://www.independent.co.uk/news/science/mindreading-rodents-scientists-show-telepathic-rats-can-communicate-using-braintobrain-8515259.html" target="blank">http://www.independent.co.uk/news/science/mindreading-rodents-scientists-show-telepathic-rats-can-communicate-using-braintobrain-8515259.html</a>  http://spacecollective.org/gamma/8310/Telepathy-by-cable Bull, Jesus and complementary horrors http://spacecollective.org/gamma/8053/Bull-Jesus-and-complementary-horrors http://spacecollective.org/gamma/8053/Bull-Jesus-and-complementary-horrors Wed, 21 Nov 2012 14:35:39 +0000 gamma 8053 <img src="http://spacecollective.org/userdata/GH93ehia/1353537298/false-photo[1].jpg" border="0" width="" height="" class="padTopBot"> The above photo has been doing the rounds on the internet with claims it is Álvaro Múnera Builes, a Colombian animal rights activist who worked briefly as a bullfighter in his youth under the name ‘El Pilarico’ in Colombia and then Spain. With the image come the words, also claiming to be from Múnera...  <a href="http://fiskeharrison.wordpress.com/2012/07/25/this-photo-is-not-what-it-seems/" target="blank">http://fiskeharrison.wordpress.com/2012/07/25/this-photo-is-not-what-it-seems/</a>  http://spacecollective.org/gamma/8053/Bull-Jesus-and-complementary-horrors Mining for electrons http://spacecollective.org/gamma/8008/Mining-for-electrons http://spacecollective.org/gamma/8008/Mining-for-electrons Thu, 25 Oct 2012 15:10:19 +0000 gamma 8008 <img src="http://spacecollective.org/userdata/GH93ehia/1351203006/electron-transport-bacteria-diagram[1].jpg" border="0" width="" height="" class="padTopBot">  <a href="http://blogs.smithsonianmag.com/science/2012/10/live-wires-newly-discovered-seafloor-bacteria-conduct-electricity/" target="blank">http://blogs.smithsonianmag.com/science/2012/10/live-wires-newly-discovered-seafloor-bacteria-conduct-electricity/</a>  http://spacecollective.org/gamma/8008/Mining-for-electrons Frog quantum receptor http://spacecollective.org/gamma/7896/Frog-quantum-receptor http://spacecollective.org/gamma/7896/Frog-quantum-receptor Thu, 13 Sep 2012 14:24:56 +0000 gamma 7896 <img src="http://spacecollective.org/userdata/GH93ehia/1347571440/PW-2012-09-13-frog[1].jpg" border="0" width="" height="" align="left" class="padRight"> A single rod photoreceptor cell taken from the eye of a frog has been fashioned into an extremely sensitive detector that can count individual photons and determine the coherence of extremely weak pulses of light. Created by researchers in Singapore, the work could lead to hybrid light detectors that incorporate living cells. <a href="http://physicsworld.com/cws/article/news/2012/sep/13/frog-photoreceptor-counts-photons" target="blank">http://physicsworld.com/cws/article/news/2012/sep/13/frog-photoreceptor-counts-photons</a> ...original at <a href="http://physics.aps.org/featured-article-pdf/10.1103/PhysRevLett.109.113601" target="blank">http://physics.aps.org/featured-article-pdf/10.1103/PhysRevLett.109.113601</a>  http://spacecollective.org/gamma/7896/Frog-quantum-receptor Job markets open new neuroscience positions http://spacecollective.org/gamma/7876/Job-markets-open-new-neuroscience-positions http://spacecollective.org/gamma/7876/Job-markets-open-new-neuroscience-positions Wed, 05 Sep 2012 15:58:42 +0000 gamma 7876 Across the United States—and in developed nations around the world—twenty-somethings are taking longer to finish school, leave home, begin a career, get married and reach other milestones of adulthood. These trends are not just anecdotal; sociologists and psychologists have gathered supporting data...  <a href="http://blogs.scientificamerican.com/brainwaves/2012/08/29/the-neuroscience-of-twenty-somethings" target="blank">http://blogs.scientificamerican.com/brainwaves/2012/08/29/the-neuroscience-of-twenty-somethings</a>  http://spacecollective.org/gamma/7876/Job-markets-open-new-neuroscience-positions Vividness detected in the brain http://spacecollective.org/gamma/7869/Vividness-detected-in-the-brain http://spacecollective.org/gamma/7869/Vividness-detected-in-the-brain Tue, 04 Sep 2012 15:37:52 +0000 gamma 7869 TORONTO, ON – Have you ever wondered why you can remember things from long ago as if they happened yesterday, yet sometimes can’t recall what you ate for dinner last night? According to a new study led by psychologists at the University of Toronto, it’s because how much something means to you actually influences how you see it as well as how vividly you can recall it later. “We’ve discovered that we see things that are emotionally arousing with greater clarity than those that are more mundane,” says Rebecca Todd, a postdoctoral fellow in U of T’s Department of Psychology and lead author of the study published recently in the Journal of Neuroscience. “Whether they’re positive – for example, a first kiss, the birth of a child, winning an award – or negative, such as traumatic events, breakups, or a painful and humiliating childhood moment that we all carry with us, the effect is the same.” “What’s more, we found that how vividly we perceive something in the first place predicts how vividly we will remember it later on,” says Todd. “We call this ‘emotionally enhanced vividness’ and it is like the flash of a flashbub that illuminates an event as it’s captured for memory.” By studying brain activity, Todd, psychology professor Adam Anderson and other colleagues at U of T, along with researchers at the University of Manchester and the University of California, San Diego found that the part of the brain responsible for tagging the emotional or motivational importance of things according to one’s own past experience – the amygdala – is more active when looking at images that are rated as vivid. This increased activation in turn influences activity in both the visual cortex, enhancing activity linked to seeing objects, and in the posterior insula, a region that integrates sensations from the body. “The experience of more vivid perception of emotionally important images seems to come from a combination of enhanced seeing and gut feeling driven by amygdala calculations of how emotionally arousing an event is,” says Todd. The researchers began by measuring the subjective experience of the vividness of perception. Taking pictures of scenes that were emotionally arousing and negative (scenes of violence or mutilation, or sharks and snakes baring their teeth), emotionally arousing and positive (mostly mild erotica), and neutral scenes (such as people on an escalator), they overlaid the images with varying amounts of “visual noise,” which looked like the snow one would see on an old television screen. The pictures were then shown to study participants who were asked to say whether each image had the same, more, or less noise than a standard image with a fixed amount of noise. “We found that while people were good at rating how much noise was on the picture relative to a standard, they consistently rated pictures that were emotionally arousing as less noisy than neutral pictures regardless of the actual level of noise,” says Todd. “When a picture was rated as less noisy, then they actually saw the picture underneath more clearly, as if there is more signal relative to noise in the emotionally arousing picture. The subjective meaning of a picture actually influenced how clearly the participants saw it.” The researchers used additional tests to rule out other explanations of their findings, such as how ‘noisy’ a picture seems due to less vibrant colours or a more complex scene. They also used eye-tracking measures to eliminate the possibility that people look at emotionally arousing images differently, causing them to rate some as more vivid. “We next wanted to see if this finding of emotionally enhanced vividness influenced memory vividness,” says Todd. “So, in two different studies, we measured memory for the images, both right after seeing them in the first place and one week later.” In the first study, 45 minutes after they did the noise task, participants were asked to write down all the details they could about pictures they remembered seeing. How much detail they remembered was a measure of vividness. In the second study, participants were shown the pictures again one week later and asked if they remembered them and, if so, how vividly they remembered them from very vague to very detailed. “Both studies found that pictures that were rated higher in emotionally enhanced vividness were remembered more vividly,” says Todd. Finally, the researchers used brain imaging measures to look at when the brain responded to emotionally enhanced vividness and what regions of the brain responded. Using electrophysiology (EEG) to measure the timing of activity in the cortex to see when the brain is sensitive to vividness, gave them a sense of whether this subjective vividness was more about seeing vividly, or thinking that it was more vivid when you’re considering it after the fact. “We found that the brain indexes vividness pretty quickly – about a 5th of a second after seeing a picture, which suggests it’s about seeing and not just thinking,” says Todd. “Emotion alters activity in the visual cortex, which in turn influences how we see.” The investigators also used functional magnetic resonance imaging (fMRI) to look at what brain regions were more active when people look at things that they perceive as more vivid because they’re emotionally important. Again, they found amygdala, visual cortex, and interoceptive cortex activity went up with increased vividness. “We know now why people perceive emotional events so vividly – and thus how vividly they will remember them – and what regions of the brain are involved,” says Todd. “Knowing that there are going to be differences among people as to how strongly they show this emotionally enhanced vividness and the strength of the brain activation patterns underlying them, could be useful in predicting an individual’s vulnerability to trauma, including intrusive memories experienced by people with post-traumatic stress disorder.” The findings are reported in the paper “Psychophysical and Neural Evidence for Emotion-Enhanced Perceptual Vividness”. Funding for the research was provided by the U.S. National Institute for Mental Health and the Canadian Institutes of Health Research.  <a href="http://media.utoronto.ca/media-releases/psychologists-link-emotion-to-vividness-of-perception-and-creation-of-vivid-memories/" target="blank">http://media.utoronto.ca/media-releases/psychologists-link-emotion-to-vividness-of-perception-and-creation-of-vivid-memories/</a>  http://spacecollective.org/gamma/7869/Vividness-detected-in-the-brain