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  • November 11, 2012
  • 08:51 PM
  • 771 views

Cut your brain some SLACK

by TheCellularScale in The Cellular Scale

Action potentials are the main means of communication between neurons, and their exact timing can be really important. But the specific timing of action potentials is really important in the auditory system, because the auditory system encodes (among other things) information about sound wave frequency. Sound waves (source)I've previously written about auditory processing with regards to the wonder that is the chicken brain, but today we will focus on timing-specificity in the mammalian brainstem. Specifically, some weird channels in the Medial Nucleus of the Trapezoid Body (the MNTB). Mammalian Auditory Brainstem (source)At the Society for Neuroscience meeting, I learned about the sodium-activated potassium channels which help the electric fish fire super-fast super-large action potentials. I was suprised to learn that sodium-activated potassium channels are located in many parts of the mammalian brain. A paper from the Kaczmarek lab at Yale explains that these sodium-activated potassium channel (SLICK and SLACK) are present in the mouse auditory brainstem and contribute to the 'temporal accuracy' of the MNTB neurons. Yang et al. (2007) record the action potentials from these neurons at a range of frequencies and show that the neuron can 'keep' up with the frequencies better when more sodium is present. Yang et al., 2007 Figure 9BIn the figure above, the 'flatter' the line, the better the 'temporal accuracy.' They also made a computational model of this neuron and ran simulations altering the sodium values and reversal potential. Yang et al., 2007 Figure 9DTheir model simulations are similar to their experimental recordings, in that more sodium results in more temporal accuary of the action potential. They confirmed that this was dues to a sodium-activated potassium channel by directly activating SLACK and seeing a similar improvement in temporal accuracy. The SLACK channel still blows my mind, but its role in helping the auditory system fire with the utmost precision actually makes a lot of sense. © TheCellularScaleYang B, Desai R, & Kaczmarek LK (2007). Slack and Slick K(Na) channels regulate the accuracy of timing of auditory neurons. The Journal of neuroscience : the official journal of the Society for Neuroscience, 27 (10), 2617-27 PMID: 17344399... Read more »

Yang B, Desai R, & Kaczmarek LK. (2007) Slack and Slick K(Na) channels regulate the accuracy of timing of auditory neurons. The Journal of neuroscience : the official journal of the Society for Neuroscience, 27(10), 2617-27. PMID: 17344399  

  • November 7, 2012
  • 10:10 AM
  • 969 views

Political Animals

by Miss Behavior in The Scorpion and the Frog

Now that we are finally on the other side of one of the longest, most expensive political campaign seasons of United States history, we find ourselves with a new mixed-bag of leaders. Our nation’s decision-makers include career politicians and new freshman politicians; they include lawyers, military members, doctors, businessmen, farmers, ministers, educators, scientists, pilots, and entertainers; they include Protestants, Catholics, Jews, Quakers, Mormons, Buddhists and Muslims; they include white Americans, African Americans, Asian Americans, and Hispanic and Latino Americans; they include men and women; they include straight and gay people; and oh yeah, they include Republicans and Democrats. With so many differences that generate so many viewpoints, how will they ever find common ground to make the kind of decisions that will move our nation in a positive direction? Hey, Look guys! We make a peace sign! Image from Wikimedia. Research into group decision-making in social animals has shown that ants, fish, birds, and bees have all discovered strategies to make intelligent group decisions. If they can do it, we can do it, right? What can we learn from these critters about harnessing the knowledge in all of us to move our whole group in the best possible direction? We will explore these insights in this post, which is a mash-up of two previous posts. To see the originals, check out Can a Horde of Idiots Be a Genius? and Why This Horde of Idiots Is No Genius.Jean-Louis Deneubourg, a professor at the Free University of Brussels, and his colleagues tested the abilities of Argentine ants (a common dark-brown ant species) to collectively solve foraging problems. In one of these studies, the ants were provided with a bridge that connected the nest to a food source. This bridge split and fused in two places (like eyeglass frames), but at each split one branch was shorter than the other, resulting in a single shortest-path and multiple longer paths. After a few minutes, explorers crossed the bridge (by a meandering path) and discovered the food. This recruited foragers, each of which chose randomly between the short and the long branch at each split. Then suddenly, the foragers all started to prefer the shortest route. How did they do that?This figure from the Goss et al 1989 paper in Naturwissemschaften shows (a) the design of a single module, (b) ants scattered on the bridge after 4 minutes (I promise they’re there), and (c) ants mostly on the shortest path after 8 minutesYou can think of it this way: a single individual often tries to make decisions based on the uncertain information available to it. But if you have a group of individuals, they will likely each have information that differs somewhat from the information of others in the group. If they each make a decision based on their own information alone, they will likely result in a number of poor decisions and a few good ones. But if they can each base their decisions on the accumulation of all of the information of the group, they stand a much better chance of making a good decision. The more information accumulated, the more likely they are to make the best possible decision.In the case of the Argentine ant, the accumulated information takes the form of pheromone trails. Argentine ants lay pheromone trails both when leaving the nest and when returning to the nest. Ants that are lucky enough to take a shorter foraging route return to the nest sooner, increasing the pheromone concentration of the route each way. In this way, shorter routes develop more concentrated pheromone trails faster, which attract more ants, which further increase pheromone concentration of the shortest routes. In this way, an ant colony can make an intelligent decision (take the shortest foraging route) without any individual doing anything more intelligent than following a simple rule (follow the strongest pheromone signal).Home is where the heart is. Photo of a bee swarm by Tom SeeleyHoneybee colonies also solve complicated tasks with the use of communication. Tom Seeley at Cornell University and his colleagues have investigated the honeybee group decision-making process of finding a new home. When a colony outgrows their hive, hundreds of scouts will go in search of a suitable new home, preferably one that is high off the ground with a south-facing entrance and room to grow. During this time, the house-hunters will coalesce on a nearby branch while they search out and decide among new home options. This process can take anywhere from hours to days during which the colony is vulnerable and exposed. But they can’t be too hasty: choosing a new home that is too small or too exposed could be equally deadly. Although each swarm has a queen, she plays no role in making this life-or-death decision. Rather, this decision is made by a consensus among 300-500 scout bees that results after an intense “dance-debate”. If a scout finds a good candidate home, she returns to the colony and performs a waggle dance, a dance in which her body position and movements encode the directions to her site and her dancing vigor relates to how awesome she thinks the site is. Some scouts that see her dance may be persuaded to follow her directions and check out the site for themselves, and if impressed, may return to the hive and perform waggle dances too. Or they may follow another scout’s directions to a different site or even strike out on their own. Over time, scouts that are less enthusiastic about their discovered site stop dancing, in part discouraged by dancers for other sites that bump heads with them and beep at them in disagreement. Eventually, the majority of the dancing scouts are all dancing the same vigorous dance. But interestingly, few scouts ever visit more than one site. Better sites simply receive more vigorous “dance-votes” and then attract more scouts to do the same. Like ants in search of a foraging path, the intensity of the collective signal drives the group towards the best decision. Once a quorum is reached, the honeybees leave their branch as a single united swarm and move into their new home, which is almost always the best site. ... Read more »

  • October 29, 2012
  • 11:00 AM
  • 771 views

Can the domains of Music Cognition and Music Information Retrieval inform each other?

by Henkjan Honing in Music Matters

In about a weeks time the 13th ISMIR (International Society for Music Information Retrieval) conference will be held. This is a conference on the processing, searching, organizing and accessing music-related data. It attracts a research community that is intrigued by the revolution in music distribution and storage brought about by digital technology which generated quite some research activity and interest in academia as well as in industry.... Read more »

Aucouturier, J., & Bigand, E. (2012) Mel Cepstrum . Proc. of the 13th International Society for Music Information Retrieval Conference, 397-402. info:/

Volk. A., & Honingh, A. (eds). (2012) Mathematical and Computational Approaches to Music: Three Methodological Reflections . Journal of Mathematics and Music, 6(2). info:/10.1080/17459737.2012.704154

  • October 28, 2012
  • 03:56 AM
  • 1,347 views

Jumping Dynamics of a Simple Robot

by Ajinkya Kamat in Brilliance Ardent



Robots fascinate all of us. While few robots are just fun toys many other robots can perform many complex tasks for us. In past decade the field of robotics has advanced by leaps and bounces making robots smarter and smarter. We have created robots, which can explore terrains- terrestrial as well as extra-terrestrial-, where even humans haven't reached. To traverse a terrain with obstacles ... Read more »

Aguilar, J., Lesov, A., Wiesenfeld, K., & Goldman, D. (2012) Lift-Off Dynamics in a Simple Jumping Robot. Physical Review Letters, 109(17). DOI: 10.1103/PhysRevLett.109.174301  

  • October 27, 2012
  • 04:49 AM
  • 547 views

Is fMRI About To Get Fifty Times Faster?

by Neuroskeptic in Neuroskeptic

According to a paper just published, a new technique of functional MRI scanning (fMRI) could soon allow neuroscientists to measure brain activity far faster: Generalized iNverse imaging (GIN): Ultrafast fMRI with physiological noise correctionAuthors Boyacioglu and Barth claim remarkable things for the technique:We find that the spatial localization of activation for GIN is comparable to an EPI protocol and that maximum z-scores increase significantly... with a high temporal resolution of 50 milliseconds.EPI, the current standard fMRI sequence, would have a temporal resolution of 2000 or 3000 milliseconds, so it's about 50 times faster.Other super-fast fMRI methods already exist (e.g. this one I blogged about), but they've generally achieved speed only at a cost: they've had to either sacrifice spatial resolution to achieve that, or limited themselves to scanning only a small fraction of the brain, or have been more subject to random noise and hence less sensitive.GIN, however, is said to cover the whole brain, with decent spatial resolution and signal-to-noise ratio. The data can be analyzed in exactly the same way as any other kind. So that's up to fifty times faster with no real drawbacks.That would be truly revolutionary - as the major limitation of fMRI at the moment is that it's much slower than other methods of recording brain activity.Check it out: this shows brain activation in response to simple visual stimuli, imaged with bog-standard EPI and GIN:So this is a big deal... if it does work, I'm sure neuroscientists the world over will be lining up to buy Boyacioglu and Barth a GIN and tonic.How does it work, and is it all it's cracked up to be? Well, I can't really say: the math is beyond me.In essence, rather than scanning the brain in 3D, slice by slice (like this), GIN only scans one 2D slice, but then manages to reconstruct the rest of the brain in 3D from just that slice, using dark, forbidden magicks... I mean mathematics. The principle is called parallel imaging and it's been around for several years, but with image quality limitations that GIN claims to have overcome.Perhaps my more technically-inclined readers will have more insightful comments.Boyacioglu R, and Barth M (2012). Generalized iNverse imaging (GIN): Ultrafast fMRI with physiological noise correction. Magnetic Resonance in Medicine PMID: 23097342... Read more »

Boyacioglu R, & Barth M. (2012) Generalized iNverse imaging (GIN): Ultrafast fMRI with physiological noise correction. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine. PMID: 23097342  

  • October 25, 2012
  • 10:15 PM
  • 677 views

Ohtsuki-Nowak transform for replicator dynamics on random graphs

by Artem Kaznatcheev in Evolutionary Games Group

We have seen that the replicator equation can be a useful tool in understanding evolutionary games. We’ve already used it for a first look at perception and deception, and the cognitive cost of agency. However, the replicator equation comes with a number of inherent assumptions and limitations. The limitation Hisashi Ohtsuki and Martin Nowak wanted [...]... Read more »

Ohtsuki H, & Nowak MA. (2006) The replicator equation on graphs. Journal of Theoretical Biology, 243(1), 86-97. PMID: 16860343  

  • October 25, 2012
  • 02:53 PM
  • 916 views

Why You Should Reject the “Rejection Improves Impact” Meme

by caseybergman in I wish you'd made me angry earlier

Over the last two weeks, a meme has been making the rounds in the scientific twittersphere that goes something like “Rejection of a scientific manuscript improves its eventual impact”.  This idea is based a recent analysis of patterns of manuscript submission reported in Science by Calcagno et al., which has been actively touted in the [...]... Read more »

  • October 24, 2012
  • 07:03 AM
  • 441 views

Scientists Find New Method to Test Bridges’ Health: Listening to Them “Singing in the Rain”

by Jaime Menchén in United Academics

It might become the most efficient and cost-effective method to check if a bridge needs repairing: Just spray the bridge’s deck with water and record the sound. That way, according to researchers at the Brigham Young University, in the US, may be possible to detect delamination (separation of structural layers) in bridges.... Read more »

  • October 22, 2012
  • 06:24 AM
  • 610 views

Large-N gauge theories on the lattice

by Marco Frasca in The Gauge Connection

Today I have found on arXiv a very nice review about large-N gauge theories on the lattice (see here). The authors, Biagio Lucini and Marco Panero, are well-known experts on lattice gauge theories being this their main area of investigation. This review, to appear on Physics Report, gives a nice introduction to this approach to [...]... Read more »

Biagio Lucini, & Marco Panero. (2012) SU(N) gauge theories at large N. arXiv. arXiv: 1210.4997v1

Marco Frasca. (2008) Yang-Mills Propagators and QCD. Nuclear Physics B (Proc. Suppl.) 186 (2009) 260-263. arXiv: 0807.4299v2

D. Gomez Dumm, & N. N. Scoccola. (2004) Characteristics of the chiral phase transition in nonlocal quark models. Phys.Rev. C72 (2005) 014909. arXiv: hep-ph/0410262v2

Marco Frasca. (2011) Chiral symmetry in the low-energy limit of QCD at finite temperature. Phys. Rev. C 84, 055208 (2011). arXiv: 1105.5274v4

  • October 18, 2012
  • 10:42 AM
  • 941 views

Searching for Extraterrestrial Microbes

by Jason Carr in Wired Cosmos

Locating thermophiles in other parts of the universe could very well aid in the search for extraterrestrial life. Most people have agreed that if life is found among the stars, it will be microbial (at least in the near-term future). Many individuals have also suggested that intelligent life forms might very well be extinct in [...]... Read more »

  • October 18, 2012
  • 07:15 AM
  • 583 views

OneZoom: Zooming in on the tree of life

by gunnardw in The Beast, the Bard and the Bot

The evolution of life is often depicted in a tree-like fashion (although, at some places, it might be more like a web). This tree analog for life’s evolution is evident in a new project to visualize the evolutionary relationships of … Continue reading →... Read more »

  • October 15, 2012
  • 10:55 AM
  • 765 views

Using METI Satellites to Find E.T.

by Jason Carr in Wired Cosmos

Cellular networks are all the rage these days. A lot of people believe that mobile technologies will eventually replace desktops/laptops entirely. Regardless, they only work with terrestrial communications networks here on Earth. What if a similar network could be built beyond our planet? Considering that all electromagnetic radiation travels at the speed of light, the [...]... Read more »

  • October 14, 2012
  • 05:55 AM
  • 780 views

Citizen science and digital platforms: folding it all the way to outer space

by Cobb & Hecht in Do You Believe In Dog?

ScienceRewired is a philanthropic initiative that aims to promote public engagement in science through digital and social technologies. Their mission is to aid non-technical science practitioners and the digital domain in working together, to look at science from new perspectives while helping educate and empower individuals to create significant positive change in the world. Their focus spreads across science education, science communication and citizen science initiatives – what’s not to love about that?!(source)I was fortunate to be awarded a scholarship to attend the day in Adelaide (730km / 450 miles away from home) by the Australian Science Communicators. The event was themed ‘Connect, Collaborate and Communicate for Change’ and intended to bring together science communicators, academics, media professionals and digital visionaries for a one day conference of debate, insight and education as a springboard for ongoing communication and action. We heard from a wide range of wonderful speakers about different digital/social media initiatives (most session content has been reported here), but what I wanted to share with you today were two really exciting and different projects that are underway using citizen science.(source)(source)What is Citizen Science anyway?Citizen science has been gaining momentum since the mid-1990’s, but just in case you haven’t heard the term before, relax. You already know what it is even if you haven’t heard the label. Simply put, it’s when amateur scientists or non-professionally-scientific people (i.e. general public) collaborate and help contribute to science. The internet has made this super easy.... Read more »

Hand Eric. (2010) Citizen science: People power. Nature, 466(7307), 687. DOI: 10.1038/466685a  

Khatib F., Cooper S., Tyka M. D., Xu K., Makedon I., Popovic Z., Baker D., & Players F. (2011) From the Cover: Algorithm discovery by protein folding game players. Proceedings of the National Academy of Sciences, 108(47), 18953. DOI: 10.1073/pnas.1115898108  

Parsons Jeffrey, Lukyanenko Roman, & Wiersma Yolanda. (2011) Easier citizen science is better. Nature, 471(7336), 37. DOI: 10.1038/471037a  

  • October 12, 2012
  • 05:35 AM
  • 898 views

What's new in Music Cognition and the Cognitive Sciences?

by Henkjan Honing in Music Matters

Why should music be of interest to cognitive scientists, and what role does it play in human cognition? ... Read more »

Pearce, Marcus, & Rohrmeier, Martin. (2012) Music Cognition and the Cognitive Sciences. Topics in Cognitive Science, 4(4), 468-484. info:/10.1111/j.1756-8765.2012.01226.x

  • October 11, 2012
  • 10:14 PM
  • 511 views

Powering electronics with stretchable batteries

by Cath in Basal Science (BS) Clarified

Potential health monitors like this one made of interlocking nanofibres are great—it’s flexible and conforms to your body. But what you don’t usually see is how these monitors might be [...]... Read more »

Abhinav M. Gaikwad, Alla M. Zamarayeva, Jamesley Rousseau, Howie Chu, Irving Derin, & Daniel A Steingart. (2012) Highly Stretchable Alkaline Batteries Based on an Embedded Conductive Fabric. Advanced Materials. DOI: 10.1002/adma.201201329  

  • October 8, 2012
  • 01:30 PM
  • 653 views

What Types of Feedback Should Students Receive?

by Eric Horowitz in peer-reviewed by my neurons

Throughout the school day there are hundreds of small reactions, judgments, and decisions that are tossed around in a student’s head. The question is, when, where, and how can students be given additional information that nudges these thoughts in directions that will lead to better learning outcomes... Read more »

Taminiau, E.M.C., Kester, L., Corbalan, G., Alessi, S.M., Moxnes, E., Gijselaers, W.H., Kirschner, P.A., & Van Merrienboer, J.J.G. (2012) Why advice on task selection may hamper learning in on-demand education. Computer in Human Behavior. DOI: 10.1016/j.chb.2012.07.028  

  • October 5, 2012
  • 12:42 AM
  • 536 views

Technology Is Rapidly Lowering the Cost of Testing

by Eric Horowitz in peer-reviewed by my neurons

People may view this as something for the good news/bad news file, but technology has quietly made it significantly easier to grade tests electronically. For example, a new paper in the Journal of Science Education and Technology highlights a system called “Eyegrade” : While most current solutions are based on expensive scanners, Eyegrade offers a [...]... Read more »

  • October 4, 2012
  • 03:50 PM
  • 578 views

A Microsyringe to Take the Pain out of Shots

by Hector Munoz in Microfluidic Future

Back when I was in sixth grade, I remember reading a little blurb in some science magazine at school that in the future we could receive shots via a method that would feel as soft as a banana peel. Although I’m now a champ at taking shots, it’s still not a bad idea. We’ve had transdermal patches (think nicotine and birth control) for some time now, but those release their medicine over a period of time. A syringe is capable of delivering a dose at once, and can take a biological sample too. Researchers from the University of Pisa have developed this ‘syringe of the future’ within ‘A minimally invasive microchip for transdermal injection/sampling applications’ in Lab on a Chip.... Read more »

  • October 1, 2012
  • 01:11 PM
  • 905 views

Does playing Solo or Vs make a Difference in Kinect or Wii? (Study)

by Stephen Yang in ExerGame Lab

If you thought yes, "you are correct Sir!" According to the current study, playing Xbox Kinect™ Reflex Ridge resulted in a 1 MET higher rating than Wii Sports Boxing, and playing multiplayer...

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  • October 1, 2012
  • 01:10 AM
  • 906 views

Does playing Solo or Vs make a Difference in Kinect or Wii? (Study)

by Stephen P. Yang, Ph.D. in ExerGame Lab

According to the current study, playing Xbox Kinect™ Reflex Ridge resulted in a 1 MET higher rating than Wii Sports Boxing, and playing multiplayer yielded a 0.5 MET increase compared to solo play... Read more »

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