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  • July 25, 2012
  • 03:30 PM
  • 976 views

Red-Eyed Rump Shaker

by Miss Behavior in The Scorpion and the Frog

A photo of a red-eyed treefrog taken by Carey James Balboa at Wikimedia.At night, male red-eyed treefrogs gather on saplings over Central American forest ponds to show off their stuff for the ladies, producing self-advertising “chack” calls. Despite the fact that they gather in groups, they defend their calling territories from flirtatious male competition. Females assess the available males and usually mate with a single male, who mounts her and clings on for dear life in a behavior called amplexus until she lays eggs that he then fertilizes. Occasionally, multiple males will try to mate with the same female at the same time, which usually results in two ticked-off male frogs. What does an angry red-eyed treefrog do, you may ask? A mildly irritated treefrog will likely produce territorial “chuckle” calls, to let rivals know this is his favorite calling-plant and they’d better step-off. But a really ticked-off red-eyed treefrog rapidly lifts and lowers his hind end in a behavior called tremulation.   "Step off, I'm doing the hump!" Video by Michael Caldwell. Not much is known about this tremulation behavior. Is it something they do just to release anxiety or is it a communication signal? If it is a communication signal, is it a visual signal or a vibrational signal or both? And what exactly might it communicate?Michael Caldwell, Karen Warkentin and Gregory McDaniel from Boston University, and Gregory Johnston from Flinders University in Australia, set out to ask the red-eyed treefrog if the tremulations were a communication signal and what they may mean. But without Dr. Doolittle’s powers of talking to the animals, how can scientists determine what and how animals are communicating?First, the researchers observed natural interactions between males at choruses in the wild and recorded everything they did. They found that male red-eyed treefrogs will often approach another male while making “chuckles” and “chacks”. These males also tremulated in every aggressive interaction observed. Some of these males kicked with their back legs and some encounters even escalated to wrestling. Eventually (usually anywhere from a minute to an hour later, but occasionally several hours later), one of the males would submit by fleeing the plant or remaining silent and motionless. The dominant male would then resume his self-advertising “chack” calls. So males use tremulation in aggressive contexts with other males, but does that mean that it is a signal?Males that won encounters tremulated more and used more "chack" and "chuckle" calls than did males that lost encounters. Figure from Caldwell et al. 2010 Current Biology paper.The researchers then conducted staged contests by placing pairs of calling males on the same sapling. In these staged contests, males showed all the same aggressive behaviors the researchers had observed in natural conditions, and most ended in a wrestling match. The males that won their encounter produced more calls and more tremulations than did males that lost their encounter (Check out the graph above). So tremulations are used in the context of aggression with other males and winners tremulate more than losers. It looks like these tremulations are an aggressive communication signal, but to know for sure, we need to know if other males respond to them. And are tremulations a visual signal, a vibrational signal, or both?So the researchers had to get creative and take it one step further: They put a robotic frog on a vibrating shaker that could mimic the visual display of a tremulation. They attached a separate vibrating shaker to the plant to mimic the vibrations of a tremulation. Now, they could look at the effects of the visual and vibrational components of the tremulation behavior separately!  Robofrog! Notice the jointed limbs and the metal rod sticking out of the robot's belly. That rod is connected to a shaker that moves the robot so it looks like he is performing a tremulation display. A separate shaker is connected to the sapling to send the vibrational component of the display. This way, the researchers can expose frogs to the visual component and the vibrational component of the tremulation display separately. Photo by Michael Caldwell.The researchers compared male red-eyed treefrogs that were exposed to (1) nothing, (2) a frog robot that does nothing, (3) a frog robot that “tremulates” with both plant vibrations and visible movement, (4) “tremulation” vibrations in the plant, without the frog robot, (5) a frog robot that moves it’s butt up and down but doesn’t produce vibrations, and (6) white noise vibrations in the plant (this is just a generic vibration). Males responded aggressively to the imitated tremulation vibrations, visual or combined but not to any of the other treatments. This suggests that tremulations are a communication signal that rival males respond to. Interestingly, males only tremulated in response to tremulation vibrations. This suggests that the vibrational component is important to sending the full aggressive signal.... Read more »

Caldwell MS, Johnston GR, McDaniel JG, & Warkentin KM. (2010) Vibrational signaling in the agonistic interactions of red-eyed treefrogs. Current biology : CB, 20(11), 1012-7. PMID: 20493702  

  • July 24, 2012
  • 06:27 AM
  • 809 views

Buddy-cops! Why evolution favours the odd couple

by John Ankers in Too Many Live Wires

Inside our cells, the battle with viruses has a lot in common with 1980s action-comedy Lethal Weapon. Both feature an unlikely pair of heroes. Each partnership - proteins and LA cops alike - has a reliable, straight-laced, by-the-book one and a loose canon, maverick one.

New research suggests that whether they're crime fighting or fighting an infection, the odd couple always gets the job done.... Read more »

Ratushny AV, Saleem RA, Sitko K, Ramsey SA, & Aitchison JD. (2012) Asymmetric positive feedback loops reliably control biological responses. Molecular systems biology, 577. PMID: 22531117  

  • July 23, 2012
  • 09:30 PM
  • 748 views

Programming playground: A whole-cell computational model

by Artem Kaznatcheev in Evolutionary Games Group

Three days ago, Jonathan R. Karr, Jayodita C. Sanghvi and coauthors in Markus W. Covert’s lab published a whole-cell computational model of the life cycle of the human pathogen Mycoplasma genitalium. This is the first model of its kind: they track all biological processes such as DNA replication, RNA transcription and regulation, protein synthesis, metabolism [...]... Read more »

Karr, J.R., Sanghvi, J.C., Macklin, D.N., Gutschow, M.V., Jacobs, J.M., Bolival, B., Assad-Garcia, N., Glass, J.I., & Covert, M.W. (2012) A whole-cell computational model predicts phenotype from genotype. Cell, 389-401. DOI: 10.1016/j.cell.2012.05.044  

  • July 19, 2012
  • 11:00 AM
  • 618 views

Detecting Unhealthy Regions in Leaf Images Pixel by Pixel

by Alejandro Mosquera in amsqr

A pixel by pixel method has been proved useful to detect unhealthy regions using leaf images. For this reason I have implemented a pixel by pixel algorithm in order to detect damaged leaf sections and to calculate leaf area in pixels.... Read more »

Pérez Rodríguez F., Camino Saco A., Mendes Lopes D.M., Rojo Alboreca A., Gómez García E. (2012) SCANNING LEAVES ALGORITHM BASED IN “RGB PIXEL BY PIXEL” METHOD. Proceedings of V European Congress of Methodology. info:/

  • July 18, 2012
  • 01:00 AM
  • 694 views

Simulated Solutions for Real Problems

by Jason Carr in Wired Cosmos

The way that people look at mathematical statistics is changing. Statistics show up in the news media left and right. People probably view graphs on a daily basis. They’re becoming desensitized to data. However, statistics will be one of the most important aspects of communication in the future. Statistics can actually allow us to predict [...]... Read more »

John W. Tukey. (1967) The Future of Data Analysis. The Annals of Mathematical Statistics, 33(1), 1-67. info:/10.1214/aoms/1177704711

  • July 16, 2012
  • 03:19 PM
  • 946 views

Building a better RoboCop

by Bradley Voytek in Oscillatory Thoughts

This week marks the 25th(!) anniversary of RoboCop, one of the hallmarks of 1980s US cinema and hero of Detroit.Detroit's soon-to-be RoboCop statue!This past weekend was also my 15th (or so) year attending Comic-Con. In a row. Because I didn't get to hear about the new RoboCop remake starring Gary Oldman, Samuel L. Jackson, and Hugh Laurie, I decided to celebrate this nerdistry my own way: by talking way to much and overthinking a plate of beans.This is me priming myself to thinking about wild ways of designing brain-computer interfaces (BCI) for my new research projects.Thus, I've decided to take a modern neuroscientific look at RoboCop. Given the huge technological advances in the 25 years since Peter Weller, Miguel Ferrer, and Red Kurtwood Smith, I believe that RoboCop would be much cooler now.So let's play with some probably very unethical human and cognitive enhancement possibilites, shall we?As a quick aside: I just found out that Peter Weller is finishing his PhD in "the history of fifteenth-century Venetian art" at UCLA, with a "minor in Ancient Greek and Roman art". And he plays jazz trumpet in a bebop sextet. Whaaaat?! Awesome.Now I'm not the first one to think about the neuroscientific implications of and possibilities of RoboCop. Apparently Ed Neumeier, writer of the original RoboCop, "was grabbed as a consultant by the US Air Force for a program called 2025. They were trying to re-imagine their role in the future and they wanted me to foster imaginative thinking." Government guys, if you're listening, this isn't legit!Look at this guy! Moral and ethical implications aside, how could you not want to be a bullet-proof, enhanced super cop!? But, cool as he is... he's a little dated. Here's a glimpse into the visual enhancements and HUD-like overlay implanted in RoboCop's nervous system:I'm pretty sure that the Miguel Ferrer overlay is not part of the standard package, but the P39-green font is your only option! We've got processes such as "MEMORY.DAT" and "ROBO UTILS" that are very important pieces of information for your robo-visual inputs.As a neuroscientist, how would I design RoboCop's enhancements... if money and was no object and the subject was totally willing?Mind you, I'm a big proponent of research ethics, so I wouldn't actually do this even if the subject were willing. Seriously. Some of this stuff is dangerous and highly speculative. But this is my place to be wildly speculative, and this is a fun way for me to talk about where the current state-of-the art in BCI stands and maybe poke some holes in the places where our neuroscientific understanding is weakest.Some of the biggest technological advancements in the last 25 years have come from the telecommunications industry. The first thing that popped into my mind was adding a GPS system into RoboCop and giving him a map overlay on top of his vision allowing for augmented reality interfaces.Essentially this would be a beefed-up Google Glass.Imagine integrating this system with something like Word Lens below:Think about how many other things one could do with such a system: alternative computer-aided visual inputs such as UV, IR, etc? Done. Automatic object/threat detection with visual overlays to exogenously capture attention? Not a problem. Draw a green line over your visual field to highlight your GPS-based route to a destination? Easy.We know that taxi drivers who have really learned the layout of their cities have bigger hippocampuses. So the obvious solution is to just inflate RoboCop's hippocampus to the size of a building! Best. Taxi driver. Ever. But really yucky oversized hippocampuses...... Read more »

Maguire EA, Gadian DG, Johnsrude IS, Good CD, Ashburner J, Frackowiak RS, & Frith CD. (2000) Navigation-related structural change in the hippocampi of taxi drivers. Proceedings of the National Academy of Sciences of the United States of America, 97(8), 4398-403. PMID: 10716738  

LaBar, Kevin S, & Cabeza, Roberto. (2006) Cognitive neuroscience of emotional memory. Nature Reviews Neuroscience, 54(1), 233-264. DOI: 10.1038/nrn1825  

Berger TW, Hampson RE, Song D, Goonawardena A, Marmarelis VZ, & Deadwyler SA. (2011) A cortical neural prosthesis for restoring and enhancing memory. Journal of neural engineering, 8(4), 46017. PMID: 21677369  

Talwar SK, Xu S, Hawley ES, Weiss SA, Moxon KA, & Chapin JK. (2002) Rat navigation guided by remote control. Nature, 417(6884), 37-8. PMID: 11986657  

  • July 16, 2012
  • 12:59 PM
  • 579 views

More Big Data to Consider: Bioimage Informatics

by Jennifer in OpenHelix

I’m not sure any more when I signed up for complementary copies of Nature Methods, but just like clockwork my copy arrives each month. If you’d like to get it too, you can apply for a subscription here (Firefox seems to work better than IE, btw). This month’s issue particularly interested me because it contains a focus on Bioimage Informatics. [...]... Read more »

Gene Myers. (2012) Why bioimage informatics matters. Nature Methods, 659-660. DOI: 10.1038/nmeth.2024  

Anne E Carpenter, Lee Kamentsky, & Kevin W Eliceiri. (2012) A call for bioimaging software usability. Nature Methods 9, 666-670. DOI: 10.1038/nmeth.2073  

Kevin W Eliceiri, Michael R Berthold, Ilya G Goldberg, Luis Ibáñez, B S Manjunath, Maryann E Martone, Robert F Murphy, Hanchuan Peng, Anne L Plant, Badrinath Roysam.... (2012) Biological imaging software tools. Nature Methods, 697-710. DOI: 10.1038/nmeth.2084  

  • July 15, 2012
  • 11:52 PM
  • 647 views

What Makes the Uncanny Valley so Unsettling?

by Eric Horowitz in peer-reviewed by my neurons

Every day we inch closer to the time when intelligent robots will be a part of everyday life. Among the many challenges we must overcome before then is gaining a better understanding of the "uncanny valley" -- the feeling of discomfort we have around humanlike robots. Thus far, most research has tended to focus on robot appearances. For example, there is evidence that humanlike robots are unnerving because their faces remind us of death, have abnormal features, and fail to align with our expectations. Still, the research has been relatively inconclusive and it's failed to uncover a more comprehensive explanation.... Read more »

  • July 11, 2012
  • 09:35 AM
  • 593 views

Dark Galaxies of the Early Universe

by Jason Carr in Wired Cosmos

Dark galaxies are small, gas-rich galaxies in the early Universe that are very inefficient at forming stars. They are predicted by theories of galaxy formation and are thought to be the building blocks of today’s bright, star-filled galaxies. Astronomers think that they may have fed large galaxies with much of the gas that later formed [...]... Read more »

Sebastiano Cantalupo, Simon J. Lilly, & Martin G. Haehnelt. (2012) Detection of dark galaxies and circum-galactic filaments fluorescently illuminated by a quasar at z. Monthly Notices of the Royal Astronomical Society. info:/arxiv.org/abs/1204.5753

  • July 8, 2012
  • 11:00 PM
  • 714 views

Critique of Chaitin’s algorithmic mutation

by Artem Kaznatcheev in Evolutionary Games Group

Last week, I reviewed Gregory Chaitin’s Proving Darwin. I concentrated on a broad overview of the book and metabiology, and did not touch on the mathematical details; This post will start touching. The goal is to summarize Chaitin’s ideas more rigorously and to address Chaitin’s comment: I disagree with your characterization of algorithmic mutations as [...]... Read more »

Chaitin, G. (2009) Evolution of Mutating Software. EATCS Bulletin, 157-164. info:/

  • July 8, 2012
  • 09:24 PM
  • 125 views

Visualizing fields of research based on readership

by Peter Kraker in Science and the Web (Peter Kraker's weblog)

Social reference management systems provide a wealth of information that can be used for the analysis of science. In this paper, we examine whether user library statistics can produce meaningful results with regards to science evaluation and knowledge domain visualization. We are conducting two empirical studies, using a sample of library data from Mendeley, the worlds largest social reference management system. Based on the occurrence of references in users libraries, we perform a large-scale impact factor analysis and an exploratory co-readership analysis. Our preliminary find- ings indicate that the analysis of user library statistics can produce accurate, timely, and content-rich results. We find that there is a significant relationship between the impact factor and the occurrence of references in libraries. Using a knowledge domain visualization based on co-occurrence measures, we are able to identify two areas of topics within the emerging field of technology-enhanced learning.... Read more »

Peter Kraker, Christian Körner, Kris Jack, & Michael Granitzer. (2012) Harnessing User Library Statistics for Research Evaluation and Knowledge Domain Visualization. Proceedings of the 21st International Conference Companion on World Wide Web , 1017-1024. DOI: 10.1145/2187980.2188236  

  • July 8, 2012
  • 04:24 PM
  • 138 views

Visualizing fields of research based on readership

by Peter Kraker in Science and the Web

I haven’t blogged lately, mostly due to the fact that I was busy moving to London. I will be with Mendeley for the next four months in the context of the Marie Curie project TEAM. My first week is over now, and I have already started to settle in thanks to the great folks at …Read More... Read more »

Peter Kraker, Christian Körner, Kris Jack, & Michael Granitzer. (2012) Harnessing User Library Statistics for Research Evaluation and Knowledge Domain Visualization. Proceedings of the 21st International Conference Companion on World Wide Web , 1017-1024. DOI: 10.1145/2187980.2188236  

  • July 6, 2012
  • 10:14 AM
  • 769 views

Advances in Neuronal Destruction

by TheCellularScale in The Cellular Scale

Destroying neurons is not difficult.  Destroying specific neurons, but leaving others intact is another story. Ablating specific neurons usually involves fancy genetic trickery, but it can also be accomplished with fancy mechanical lasers! Laser near cell (source)A new study published in PNAS (Hayes et al., 2012) uses the cells own rhythm generating properties to target the neurons for destruction.Specifically, Hayes et al. is investigating the breathing neurons. These neurons are in the Pre-Botzinger Complex (preBotC) of the Medulla and they control the inhalation phase of breathing.  They work together as a complex to generate rhythms even in a brain slice.  Using a calcium-sensitive dye, Hayes et al. could tell which neurons were participating in the rhythm generation. The breathing neurons show specific calcium patterns, increasing and decreasing with a frequency of 0.15-0.5Hz.  The breathing neurons are located and the specific spatial coordinates of each neuron is saved.  A mechanically controlled laser can then automatically target each specific neuron for destruction (red dots in figure below).  Hayes et al., 2012 Figure 1Because silencing the neurons (NK1R-containing) in the preBotC completely stops breathing, they wanted to see how many neurons could be destroyed before the rhythm stopped.  And they wanted to see how it stopped.  Is there some magic number of cells that are needed to maintain the rhythmic output? or does the rhythm slowly decrease in amplitude?  So measuring the XII nerve for output, they began randomly destroying the rhythmic cells one by one. They found that destroying these neurons one by one caused a decrease in amplitude and frequency of the XII nerve output and eventually stopped it entirely.  It took about 120 neurons to completely stop the rhythm, but the weird thing is that even after destroying 120 neurons, the rhythm continued for about half an hour.  The mechanisms underlying this delay are not completely clear, but the authors attribute it to the slow effects of a decrease in mGluR stimulation.  This new technique is pretty exciting because it allows the sequential deletion of specific cells.  Even the study erasing memories cell by cell didn't actually delete the cells one at a time. This technique is especially interesting for investigating the way that a collection of individual cells create emergent network properties.  Now questions like 'how many cells are needed to form or maintain a functional network?' and 'which cells are necessary for the network's function?' can be answered.  © TheCellularScaleHayes JA, Wang X, & Del Negro CA (2012). Cumulative lesioning of respiratory interneurons disrupts and precludes motor rhythms in vitro. Proceedings of the National Academy of Sciences of the United States of America, 109 (21), 8286-91 PMID: 22566628... Read more »

Hayes JA, Wang X, & Del Negro CA. (2012) Cumulative lesioning of respiratory interneurons disrupts and precludes motor rhythms in vitro. Proceedings of the National Academy of Sciences of the United States of America, 109(21), 8286-91. PMID: 22566628  

  • July 3, 2012
  • 09:13 AM
  • 716 views

Artificial Cerebellum in Robotics Developed

by Jason Carr in Wired Cosmos

University of Granada researchers have developed an artificial cerebellum (a biologically-inspired adaptive microcircuit) that controls a robotic arm with human-like precision. The cerebellum is the part of the human brain that controls the locomotor system and coordinates body movements.... Read more »

  • July 2, 2012
  • 04:35 AM
  • 531 views

How 16,000 Processors Learned to Actually ‘See’

by United Academics in United Academics

In their search for knowledge on complex data processing, the group has created a huge surrogate neural-like network of 16,000 connected computer processors, which share about one billion connections.... Read more »

Quoc, V. Le, Marc’Aurelio Ranzato, Rajat Monga, Matthieu Devin, Kai Chen, Greg S. Corrado, Jeff Dean, Andrew Y. Ng. (2012) Building High-level Features Using Large Scale Unsupervised Learning. arxiv.org. info:/

  • June 29, 2012
  • 04:42 PM
  • 689 views

How fireworks light up the sky

by Cath in Basal Science (BS) Clarified

Many countries/regions will be celebrating their national/independence day over the weekend and into next week, so you’ll likely have a chance to see some fireworks whether in person, on television, [...]... Read more »

  • June 29, 2012
  • 01:00 PM
  • 794 views

Is Chaitin proving Darwin with metabiology?

by Artem Kaznatcheev in Evolutionary Games Group

Algorithmic information theory (AIT) allows us to study the inherent structure of objects, and qualify some as ‘random’ without reference to a generating distribution. The theory originated when Ray Solomonoff (1960), Andrey Kolmogorov (1965), and Gregory Chaitin (1966) looked at probability, statistics, and information through the algorithmic lens. Now the theory has become a central [...]... Read more »

Chaitin, G. (2009) Evolution of Mutating Software. EATCS Bulletin, 157-164. info:/

  • June 27, 2012
  • 07:20 AM
  • 308 views

Herkent u deze melodie? [Dutch]

by Henkjan Honing in Music Matters

Je zit in je auto en draait wat aan de knop van de radio. Je hoort al snel of bepaalde muziek je bevalt of niet. Je herkent een stem, een liedje of zelfs de uitvoering ervan. Iedereen doet het, iedereen kan het. En vaak ook nog eens razendsnel: sneller dan een noot gemiddeld klinkt.Als u gevraagd zou worden om naar een reeks muziekfragmenten van 0,2 seconde te luisteren, zal blijken dat u met gemak aan kan geven welk fragment klassiek, jazz, R&B of pop is (zie luistertest). Een snippertje geluid geeft ons toegang tot de herinnering aan eerder gehoorde muziek, ook al hebben we deze serie noten nog nooit eerder gehoord. Die herinnering kan heel specifiek zijn: aan een liedje van Björk, bijvoorbeeld. Maar ze kan ook heel algemeen zijn: we herkennen een bepaald genre: klassiek, country, jazz. De nuances in klankkleur, karakteristiek voor een liedje of een heel genre, zitten kennelijk op een abstracte manier in ons geheugen opgeslagen. Daarom is de draaiknop (of tiptoets) van de autoradio zo’n succesvolle interface geworden…Vandaag verschenen er verschillende items in de media n.a.v. van een stukje in Volkskrant over de oorwurm en de hype rond Song Pop, een app die gebruik maakt van het hierboven beschreven muzikale talent dat we allemaal delen: het razendsnel herkennen van muziek.Over oorwurm: Volkskrant, NOS op 3 Over Song Pop App: Editie NL   Gjerdingen, Robert O., & Perrott, D. (2008). Scanning the Dial: The Rapid Recognition of Music Genres Journal of New Music Research, 37 (2), 93-100 DOI: 10.1080/09298210802479268... Read more »

Gjerdingen, Robert O., & Perrott, D. (2008) Scanning the Dial: The Rapid Recognition of Music Genres. Journal of New Music Research, 37(2), 93-100. DOI: 10.1080/09298210802479268  

  • June 25, 2012
  • 09:11 AM
  • 322 views

Why does a well-tuned modern piano not sound out-of tune?

by Henkjan Honing in Music Matters

Karlheinz Stockhausen is listening."Neue Musik ist anstrengend", wrote Die Zeit some time ago: "Der seit Pythagoras’ Zeiten unternommene Versuch, angenehme musikalische Klänge auf ganzzahlige Frequenzverhältnisse der Töne zurückzuführen, ist schon mathematisch zum Scheitern verurteilt. Außereuropäische Kulturen beweisen schließlich, dass unsere westliche Tonskala genauso wenig naturgegeben ist wie eine auf Dur und Moll beruhende Harmonik: Die indonesische Gamelan-Musik und Indiens Raga-Skalen klingen für europäische Ohren schräg."The definition of music as “sound” wrongly suggests that music, like all natural phenomena, adheres to the laws of nature. In this case, the laws would be the acoustical patterns of sound such as the (harmonic) relationships in the structure of the dominant tones, which determine the timbre. This is an idea that has preoccupied primarily the mathematically oriented music scientists, from Pythagoras to Hermann von Helmholtz. The first, and oldest, of these scientists, Pythagoras, observed, for example, that “beautiful” consonant intervals consist of simple frequency relationships (such as 2:3 or 3:4). Several centuries later, Galileo Galilei wrote that complex frequency relationships only “tormented” the eardrum. But, for all their wisdom, Pythagoras, Galilei, and like-minded thinkers got it wrong. In music, the “beautiful,” so-called “whole-number” frequency relationships rarely occur—in fact, only when a composer dictates them. The composer often even has to have special instruments built to achieve them, as American composer Harry Partch did in the twentieth century. Contemporary pianos are tuned in such a way that the sounds produced only approximate all those beautiful “natural” relationships. The tones of the instrument do not have simple whole number ratios, as in 2:3 or 3:4. Instead, they are tuned so that every octave is divided into twelve equal parts (a compromise to facilitate changes of key). The tones exist, therefore, not as whole number ratios of each other, but as multiples of 12√2 (1:1.05946).According to Galilei, each and every one of these frequency relationships are “a torment” to the ear. But modern listeners experience them very differently. They don’t particularly care how an instrument is tuned, otherwise many a concertgoer would walk out of a piano recital because the piano sounded out of tune. It seems that our ears adapt quickly to “dissonant” frequencies. One might even conclude that whether a piano is “in tune” or “out of tune” is entirely irrelevant to our appreciation of music. [fragment from Honing, 2011.]Julia Kursell (2011). Kräftespiel. Zur Dissymmetrie von Schall und Wahrnehmung. Zeitschrift für Medienwissenschaft, 2 (1), 24-40 DOI: 10.4472_zfmw.2010.0003Honing, H. (2012). Een vertelling. In S. van der Maas, C. Hulshof, & P. Oldenhave (Eds.), Liber Plurum Vocum voor Rokus de Groot (pp. 150-154). Amsterdam: Universiteit van Amsterdam (ISBN 978-90-818488-0-0).Whalley, Ian. (2006). William A. Sethares: Tuning, Timbre, Spectrum, Scale (Second Edition). Computer Music Journal, 30 (2) DOI: 10.1162/comj.2006.30.2.92... Read more »

Julia Kursell. (2011) Kräftespiel. Zeitschrift für Medienwissenschaft, 2(1), 24-40. DOI: 10.4472_zfmw.2010.0003  

  • June 21, 2012
  • 03:21 PM
  • 825 views

Neuron-controlled robots: reverse-cyborgs

by TheCellularScale in The Cellular Scale

Last post we discussed robotically controlled biology.  In this post we will talk about biologically controlled robots.The Hybrot: a rat neuron controlled robotIn 2001, S. Potter published a paper on the "Animat". A set of cultured neurons on a multi-electrode array (MEA, purple circle in above image) interfaced with a simulated robot.  That is, not a physical moving around robot as pictured above, but a computer program simulating what a robot/animal could do.  They made a virtual room for the animat to 'explore'. (If you can make a virtual environment for a worm, I suppose you can make one for a petri dish of cultured neurons) The signal from the cultured neurons determined where the animat went. If one group of neurons fired, the animat moved left, if another group fired it moved forward, and so forth. (The actual equations translating neuronal activity to animat movement were more complex than this, but you get the idea.)  So here's the really cool thing: When the animat 'hit a wall', a set of neurons were stimulated with an electric pulse. They also gave the cultured neurons a sort of vestibular system, stimulating a different area depending on which direction the Animat was traveling.Although this Animat study was using a simulated environment and a simulated robot, using cultured neurons to control an actual robot was only a matter of time.  Neurons are somehow even cooler when they are combined with robots, no?So what I think is really exciting about this reverse-cyborg system is that you can study the formation of neuronal networks in response to realistic experience. The feedback system used in the Animat could reveal how natural synaptic plasticity and other network-forming processes could organize a set of neurons. I am particularly interested in the effects of neuromodulation on these neurons.  If they form a certain kind of network under normal conditions, how would that change if they were bathed in dopamine during the 'experience' or serotonin, or whatever. (Pick your favorite neurotransmitter).It is easy to think that this robot has a 'brain' but really the cultured neurons are not organized like the brain at all.  Watching a network form in a dish is fascinating and can yield information about how neural networks form in general, but don't assume that this will tell us how networks actually form in an actual brain.  Robots sure are cute (source)These methods can be used to discover really interesting things about neurons and networks, but other kinds of study (such as ones using real, intact brains) are need to find out what actually happens. © TheCellularScaleDemarse TB, Wagenaar DA, Blau AW, & Potter SM (2001). The Neurally Controlled Animat: Biological Brains Acting with Simulated Bodies. Autonomous robots, 11 (3), 305-310 PMID: 18584059... Read more »

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