Saturday, December 26, 2009

It's all in your head. No, really: How mental imagery training aids perceptual learning.

Practice makes perfect. But imaginary practice? Elisa Tartaglia of the Laboratory of Psychophysics at Switzerland’s Ecole Polytechnique Federale de Lausanne (EPFL) and team show that perceptual learning—learning by repeated exposure to a stimulus—can occur by mental imagery as much as by the real thing. The results, published in Current Biology, suggest that thinking about something over and over again could actually be as good as doing it.

"When trained, radiologists are able to detect anomalies on medical images which are extremely hard to detect for untrained people,” Tartaglia says. “The results of our study would predict that mental imagery training, hence, repeatedly mentally visualizing the anomalies that one wants to detect, would be sufficient to become able to detect them.”

In a series of experiments, the scientists asked some participants to practice identifying which line, the right or the left in a series of parallel lines, a central line was closest to and to identify it by pushing the correct button. In follow-up, “post-training” exercises, these participants improved their baseline performance significantly. But so did another set of volunteers who, instead of practicing with all three lines in training, were instead asked to imagine the bisecting line’s proximity based on an audio tone. This group also improved their performance significantly in further testing, meaning that “imagery training” was sufficient for perceptual learning.

Some experts question the relevance of mental imagery in this kind of learning, which is generally assumed to be driven by stimulus processing—synapses firing in response to a physical cue. Here, the researchers show that perceptual learning can also occur by mental imagery, i.e., in the absence of physical stimulation. The results help shine a light on what has been an ongoing puzzle in the field and suggest an overlap in how—and possibly where—mental imagery affects perceptual learning.

from: EPFL

Tuesday, December 8, 2009

Cat Fight Brews Over Cat Brain


The Story begins when Modha announced that his team has completed simulation of a cat brain. At this time Henry Markram a leading neuroscientist who is trying to make a detailed simulation model of the human brain took umbrage at their work and he wrote the following letter. He called their work a hoax.


Dear Bernie,

You told me you would string this guy up by the toes the last time Mohda made his stupid statement about simulating the mouse's brain.

I thought that having gone through Blue Brain so carefully, journalists would be able to recognize that what IBM reported is a scam - no where near a cat-scale brain simulation, but somehow they are totally deceived by these incredible statements.

I am absolutely shocked at this announcement. Not because it is any kind of technical feat, but because of the mass deception of the public.

1. These are point neurons (missing 99.999% of the brain; no branches; no detailed ion channels; the simplest possible equation you can imagine to simulate a neuron, totally trivial synapses; and using the STDP learning rule I discovered in this way is also is a joke).

2. All these kinds of simulations are trivial and have been around for decades - simply called artificial neural network (ANN) simulations. We even stooped to doing these kinds of simulations as bench mark tests 4 years ago with 10's of millions of such points before we bought the Blue Gene/L. If we (or anyone else) wanted to we could easily do this for a billion "points", but we would certainly not call it a cat-scale simulation. It is really no big deal to simulate a billion points interacting if you have a big enough computer. The only step here is that they have at their disposal a big computer. For a grown up "researcher" to get excited because one can simulate billions of points interacting is ludicrous.

3. It is not even an innovation in simulation technology. You don't need any special "C2 simulator", this is just a hoax and a PR stunt. Most neural network simulators for parallel machines can can do this today. Nest, pNeuron, SPIKE, CSIM, etc, etc. all of them can do this! We could do the same simulation immediately, this very second by just loading up some network of points on such a machine, but it would just be a complete waste of time - and again, I would consider it shameful and unethical to call it a cat simulation.

4. This is light years away from a cat brain, not even close to an ants brain in complexity. It is highly unethical of Mohda to mislead the public in making people believe they have actually simulated a cat's brain. Absolutely shocking.

5. There is no qualified neuroscientist on the planet that would agree that this is even close to a cat's brain. I see he did not stop making such stupid statements after they claimed they simulated a mouse's brain.

6. You should also ask Mohda where he got the notion of "reverse engineering" from, when he does not even know what it means - look the the models - this has nothing to do with reverse engineering. And mouse, rat, cat, primate, human - ask him where he took that from? Simply a PR stunt here to ride on Blue Brain.

That IBM and DARPA would support such deceptive announcements is even more shocking.

That the Bell prize would be awarded for such nonsense is beyond belief. I never realized that such trivial and unethical behavior would actually be rewarded. I would have expected an ethics committee to string this guy up by the toes.

I suppose it is up to me to let the "cat out of the bag" about this outright deception of the public.

Competition is great, but this is a disgrace and extremely harmful to the field. Obviously Mohda would like to claim he simulated the Human brain next - I really hope someone does some scientific and ethical checking up on this guy.

All the best,

Henry

the letter is from IEEE Spectrum

Wednesday, December 2, 2009

When coulorfulBrain neurons fire.

Hi
Iv'e just finished reading an article in ieee spectrum. This article fired some of my neurons(neurons who responsible for writing in this weblog).So I start writing here again.
I will uplaod this article in next post.
Good luck

Sunday, September 13, 2009

Changiz

In the way of BlueBrain; yesterday me and 2 of my best friends meet Mr. Eslahchi a bioinformatics scientist. He explained us kindly. a huge thanks to him.^_^

Monday, September 7, 2009

Wireless

Thank you from bottom of my heart to inventors of wirless internet ;)

Friday, September 4, 2009

got cold

I've got cold. Good time to rest and not going to english class. :)

Sunday, August 30, 2009

yesterday I decided to write in this weblog regularly. so this is the beginning.
here is something that makes me to start writing yesterday:

I’ve just finished “Kiss the lovely face of God” written by Mostafa Mastoor. I have a strange feeling.
Something is wrong I don’t know what it is.
I think the book didn’t tell something. Something important. Very important.
Something that will give us the real meaning of life.

Monday, February 23, 2009

first if firsts

Hi
How do you do?This is my first post on an English weblog.