The brain of the fly - a high-speed computer

Jul 12, 2010
Seeing into a fly’s brain: Neurobiologists use state-of-the-art methods to observe the activity of nerve cells while the fly sees moving stripe patterns on a LED screen (left). This technique enables the scientists to observe the response of single cells in the brain area which processes motion information (right, scale = 20 micrometer). Image: Max Planck Institute of Neurobiology

(PhysOrg.com) -- Neurobiologists use state-of-the-art methods to decode the basics of motion detection.

What would be the point of holding a soccer world championship if we couldn't distinguish the ball from its background? Simply unthinkable! But then again, wouldn't it be fantastic if your favourite team's striker could see the movements of the ball in slow motion! Unfortunately, this advantage only belongs to flies. The minute brains of these aeronautic acrobats process visual movements in only fractions of a second. Just how the of the fly manages to perceive motion with such speed and precision is predicted quite accurately by a . However, even after 50 years of research, it remains a mystery as to how nerve cells are actually interconnected in the brain of the fly.

Scientists at the Max Planck Institute of Neurobiology are now the first to successfully establish the necessary technical conditions for decoding the underlying mechanisms of motion vision. The first analyses have already shown that a great deal more remains to be discovered ( July 11, 2010).

Back in 1956, a mathematical model was developed that predicts how movements in the brain of the fly are recognized and processed. Countless experiments have since endorsed all of the assumptions of this model. What remains unclear, however, is the question as to which nerve cells are wired to each other in the fly brain for the latter to function as predicted in the model. "We simply did not have the technical tools to examine the responses of each and every cell in the fly's tiny, but high-powered brain", as Dierk Reiff from the Max Planck Institute of Neurobiology in Martinsried explains. That is hardly surprising, considering the minute size of the brain area that is responsible for the fly's . Here, one sixth of a cubic millimetre of brain matter contains more than 100,000 nerve cells - each of which has multiple connections to its neighbouring cells. Although it seems almost impossible to single out the reaction of a certain cell to any particular movement stimulus, this is precisely what the neurobiologists in Martinsried have now succeeded in doing.

The brain of the fly beats any computer

The electrical activity of individual nerve cells is usually measured with the aid of extremely fine electrodes. In the fly, however, most of the nerve cells are simply too small to be measured using this method. Nevertheless, since the fly is the animal model in which motion perception has been studied in most detail, the scientists were all the more determined to prize these secrets from the insect's brain. A further incentive is the fact that, albeit the number of nerve cells in the fly is comparatively small, they are highly specialized and process the image flow with great precision while the fly is in flight. Flies can therefore process a vast amount of information about proper motion and movement in their environment in real time - a feat that no computer, and certainly none the size of a fly's brain, can hope to match. So it's no wonder that deciphering this system is a worth-while undertaking.

Fluorescence molecules and state-of-the-art microscopes

"We had to find some way of observing the activity of these tiny nerve cells without electrodes", Dierk Reiff explains one of the challenges that faced the scientists. In order to overcome this hurdle, the scientists used the fruit fly Drosophila melanogaster and some of the most up-to-date genetic methods available. They succeeded in introducing the indicator molecule TN-XXL into individual nerve cells. By altering its fluorescent properties, TN-XXL indicates the activity of nerve cells.

To examine how the brains of fruit flies process motion, the neurobiologists presented the insects with moving stripe patterns on a light-diode screen. The nerve cells in the flies' brains react to these LED light impulses by becoming active, thus causing the luminance of the indicator molecules to change. Although TN-XXL's luminance changes are much higher than that of former indicator molecules, it took quite some time to capture this comparatively small amount of light and to separate it from the LED-light impulse. After puzzling over this for a while, however, Dierk Reiff solved the problem by synchronizing the 2-photon-laser microscope with the LED-screen at a tolerance of merely a few microseconds. The TN-XXL signal could subsequently be separated from the LED-light and selectively measured using the 2-photon-microscope.

The cells behind the model

"At long last, after more than 50 years of trying, it is now technically possible to examine the cellular construction of the motion detector in the brain of the fly", reports a pleased Alexander Borst, who has been pursuing this goal in his department for a number of years. Just how much remains to be discovered was realized during the very first application of the new methods. The scientists began by observing the activity of cells known as L2-cells which receive information from the photoreceptors of the eye. The photoreceptors react when the light intensity increases or decreases. The reaction of the L2-cells is similar in that part of the cell where the information from the photoreceptor is picked up. However, the neurobiologists discovered that the L2-cell transforms these data and in particular, that it relays information only about the reduction in light intensity to the following . The latter then calculate the direction of motion and pass this information on to the flight control system. "This means that the information "light on" is filtered out by the L2-cells", summarizes Dierk Reiff. "It also means, however, that another kind of cell must pass on the "light on" command, since the fly reacts to both kinds of signals."

Now that the first step has been taken, the scientists intend to examine - cell by cell - the motion detection circuitry in the fly brain to explain how it computes motion information at the cellular level. Their colleagues from the joint Robotics project are eagerly awaiting the results.

Explore further: Functional brain imaging reliably predicts which vegetative patients have potential to recover consciousness

More information: Visualizing retinotopic half-wave rectified input to the motion detection circuitry of Drosophila. Dierk F. Reiff, Johannes Plett, Marco Mank, Oliver Griesbeck, Alexander Borst, Nature Neuroscience, online publication from July 11, 2010

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Hunnter
not rated yet Jul 12, 2010
The people who put rat cells on electrodes should try this with fly brain cells in a mini helicopter / robotic fly.
Would make for some interesting research.
JamesThomas
5 / 5 (3) Jul 12, 2010
When we start to acknowledge and respect the brilliance within a fly's brain, one has to pause for the briefest of moments before swatting it -- by then it has flown into some other room performing countless acts of aerodynamic wizardry along the way....all the while laughing at how lethargic and stupid we are.
Little shit-eating bastards, I swear I'll get the next one!
mabarker
1.5 / 5 (8) Jul 12, 2010
The pattern in these amazing stories seems to be the same: (1) the sophistication is greater than anyone ever thought, and (2) macroevolution, if mentioned at all, is an afterthought tacked onto the story. I see no explanatory power - but macroevolution is merely assumed.
Getting through J. Thomas' obscenities & frustration, we can see the reason for the f/flies ability: the retinotopic half-wave rectified input to their motion detection circuitry. Random mutations have exactly nothing to do with this intelligent design.
HaveYouConsidered
4.3 / 5 (6) Jul 12, 2010
Left to operate over only a few hundred or thousands of generations, genetic programming does indeed produce significant optimizations with only random mutation, genetic crossover, and some fitness function (selection pressure) that chooses the fitest members for the next generation: no intelligent designer needed. Over 3.8 billion years, and countless generations, yes, a fruit fly emerges, also without an intelligent designer. And after all, were there one, you'd have to explain where it came from, mabarker.
mabarker
1 / 5 (6) Jul 13, 2010
Just as I expected, evolutionists (*considered*) resort to hand waving to *explain* the enormous complexity we see in the neurobiology of the f/fly.
Presto! *Over 3.8 billion years, and countless generations, yes, a fruit fly emerges . . .* This is nothing more than a required philosophical statement, void of empirical validation.
*Fitness function*, Considered, can mean anything the darwinist wants it to mean. It's a nebulous term. Darwinist J. Beatty said, *The precise meaning of fitness has yet to be settled, in spite of the fact - or perhaps because of the fact - that the term is so central to evolutionary thought.* In late Oct '02 evolutionist J. Brookfield wrote a primer on fitness, but failed. See also E.F. Keller's outstanding 2-pg essay on Fitness: reproductive ambiguities.
No 1 says computers assemble randomly. The above article states, *a feat that no computer, and certainly none the size of a fly's brain, can hope to match . . .* Intricate design means a Designer.
otto1923
3 / 5 (4) Jul 13, 2010
Intricate design means a Designer.
Garbled post means a brainless godlover. You want rational debate youre going to have to compose a more readable post. But I doubt you want rational debate, do you? You just want answers, NOW.

And of course, you want to live forever with all your dead relatives and so would believe and say anything to ensure that, wouldnt you?
mabarker
1 / 5 (4) Jul 13, 2010
Y'know otto, if I had paid you to write what you wrote (above) it couldn't work out any better for me! Thank You, my intolerant friend.
Your vitriol clearly shows your bigotry toward people of faith. You best attend some sensitivity training.
A more readable post? Let's see: 1. I showed first of all that *considered* did not address how the f/fly neurobiology specifically evolved. 2. I then listed 3 evolutionists who admitted (to their credit) that *fitness* is both vague & undefined. 3. I concluded that no amount of random interactions (and *selection pressure*) would form a computer and that a f/fly brain is infinitely more complex - a testimony to the creativity of God.
See you in Church!
otto1923
5 / 5 (2) Jul 13, 2010
You guys show up and spout your tripe where it is neither wanted nor appropriate, and you will be slammed. You think just because there have been so many of you for so long that you must be right? So do jews and islamists.

(*considered*)
And what do the little stars mean? Some secret coven sign? Or you just trying to be creative like the people who made up the crap in the bible?

Try this:
http://www.youtub...=related
-Maybe god would like it.

Keep your bizarre neverneverland fantasies to yourself.
frajo
5 / 5 (3) Jul 14, 2010
You guys show up and spout your tripe where it is neither wanted nor appropriate, and you will be slammed.
You don't know how right you are :)
Unfortunately, but not surprisingly, you omit to mention that "wanted" and "appropriate" vary from reader to reader.
Thus you'll just have to live with the competition of Bible believers and their differing exegeses. And I'll have to live with your superstitious belief of an Empire. The main difference being that I've no need to become impolite.
Ethelred
4.8 / 5 (4) Jul 14, 2010
the sophistication is greater than anyone ever thought
I didn't see that in the article. The model is 50 years old and predicts the behavior of flies, so you statement is just plain wrong.
macroevolution, if mentioned at all, is an afterthought tacked onto the story. I see no explanatory power - but macroevolution is merely assumed
Not even in the article. After two months away surely you could have found something that was about evolution?

However since YOU brought it up. Macroevolution was proved to happen long ago. No assumption is needed.
Random mutations have exactly nothing to do with this intelligent design
Random mutations PLUS natural selection, which is NOT random, has EVERYTHING to do with it.

Just why do you insist on pretending that randomness is all there is to evolution. It has been pointed out time and again for years on this site to you that natural selection is inherently non-random.

Surely you should learned that by now.

Ethelred
Ethelred
5 / 5 (3) Jul 14, 2010
evolutionists (*considered*) resort to hand waving
It is not hand waving to invoke a process that is known to exist.
the enormous complexity we see in the neurobiology of the f/fly
So enormous that it was modeled back in the 50's. Flies just aren't that complex. A 100,000 cells to run everything.
*Fitness function*, Considered, can mean anything the darwinist wants it to mean. It's a nebulous term.
Bull. Fitness is what leads to survival and reproduction. Quoting people out of context won't make it any more difficult to define than that.
above article states, *a feat that no computer, and certainly none the size of a fly's brain, can hope to match
Yet. Not even tried yet. However we DO have computers that fly remote vehicles. Right now.
Intricate design means a Designer.


But complex biology does not. Using loaded words like 'design' doesn't turn nonsense into truth.

Ethelred
Ethelred
5 / 5 (2) Jul 14, 2010
I showed first of all that *considered* did not address how the f/fly neurobiology specifically evolved.
He didn't claim to be specific.
2. I then listed 3 evolutionists who admitted (to their credit) that *fitness* is both vague & undefined.
You mean you took quote mined 3 people and left out the context. My definition is not vague so lets use that since any evolutionist will agree that it is correct.
3I concluded that no amount of random interactions (and *selection pressure*) would form a computer


And on that I agree. After all computers are BUILT not grown.
a f/fly brain is infinitely more complex
So you think 1 2 3 infinity isn't a metaphor? Computers are MORE complex than a fly's brain. Billions of transistors not a mere 100,000 cells.
a testimony to the creativity of God.
So god if god is infinitely complex then using YOUR numbers god has 100,000 cells to think with.

So maybe we will see you in a math class.

Ethelred
Ethelred
5 / 5 (3) Jul 14, 2010
Otto

I have to agree with Frajo on this. You were impolite. True Mabarker engages in mendacious terms like 'random evolution' quote mines to distort meaning and doesn't have a clue as to what constitutes 'infinitely more complex' but that is no excuse for being a BLEEP about it.

Ma hates reason and leaves when reasoned with. So be reasonable and Ma will go away.

Oh yes I have space.

Brevity if for soulless twits.

Mabarker - please learn something here even if you continue to refuse to learn biology and what infinity means PLEASE do learn to use white space even with the stupid limit. It will make you ever so much more legible.

Ethelred
Skeptic_Heretic
3.7 / 5 (3) Jul 14, 2010
Just as I expected, evolutionists (*considered*) resort to hand waving to *explain* the enormous complexity we see in the neurobiology of the f/fly.
Presto! *Over 3.8 billion years, and countless generations, yes, a fruit fly emerges . . .* This is nothing more than a required philosophical statement, void of empirical validation.

Yeah it's far more rational to believe a wizard did it. Isn't it, mabarker?

Seriously, go get an education and stop spouting bronze age nonsense.
frajo
5 / 5 (1) Jul 14, 2010
Computers are MORE complex than a fly's brain. Billions of transistors not a mere 100,000 cells
I'm not so sure about that. While I don't know whether the number of synapses of a fly's neuron is 10**5 as that of a human brain neuron, I do assume that there are definitely more connections between the fly's (10**5) neurons than between the (billions of) transistors in a modern chip. Thus the question which apparatus is the more complex one seems still to be open.
otto1923
not rated yet Jul 14, 2010
Your vitriol clearly shows your bigotry toward people of faith. You best attend some sensitivity training.
Impolite. 'Wie du mir, so ich dir.' It's in the bible. Inventive *punctuation* really drives Otto up the wall.
3. I concluded that no amount of random interactions (and *selection pressure*) would form a computer and that a f/fly brain is infinitely more complex - a testimony to the creativity of God.
AND Otto was baited with outrageous illogic.
frajo
4 / 5 (2) Jul 14, 2010
Inventive *punctuation* really drives Otto up the wall.
An interesting contrast to your usually inventive German and Latin grammar. :)
Javinator
5 / 5 (2) Jul 14, 2010
Computers are MORE complex than a fly's brain. Billions of transistors not a mere 100,000 cells
I'm not so sure about that. While I don't know whether the number of synapses of a fly's neuron is 10**5 as that of a human brain neuron, I do assume that there are definitely more connections between the fly's (10**5) neurons than between the (billions of) transistors in a modern chip. Thus the question which apparatus is the more complex one seems still to be open.


I think it depends on how you define complexity. After all, a Goldberg machine to turn on a light switch can be quite complex, however it is not faster than simply walking over and flipping the switch.
Ethelred
not rated yet Jul 15, 2010
I do assume that there are definitely more connections between the fly's (10**5) neurons than between the (billions of) transistors in a modern chip
10,000 cells with a thousand connections each, one connection for every ten cells, still is only 10 MILLION connections You would need a thousand switches per connection to reach a billion switches.

The fly's speed advantage is that only a tiny fraction of the cells are engaged in processing visual information and they are quite close together. And they don't really do much work in flies.

To give an example, with an insect know for serious survival skills, the cockroach. When startled they simply head for anything dark. Don't think so? Try this.

When you see one of the annoying things near your feet, I recommend shoes for this, just lift up your toes a bit to make, oh say, a half inch gap beneath the front of your foot. Startle roach, watch the clever roach run RIGHT UNDER YOUR FOOT. Exeunt roach, stage squished.

Ethelred
Ethelred
not rated yet Jul 16, 2010
Oops, I made a tiny ereror there. Just of by one number. That should have been 100,000 not 10,000 just one order magnitude. 100 million is still a quite a ways from 1 billion or so.

And notice that Ma is gone now. Can't deal with reason. Be polite and rational and Ma just quits. I have TRIED to Ma to engage.

Ethelred
frajo
not rated yet Jul 16, 2010
100 million is still a quite a ways from 1 billion or so.
I tend to agree with Javinator - it's the question how we define "complexity". As it seems, the 10**11 neurons with their 10**4 synapses per neuron are not alone in the human brain - they are interconnected with 10**12 astrocytes.
I don't know about synapses and astrocytes in a fly's brain, but i do know that this tiny thing works 2 magnitudes faster than my apparatus. If this is due to simplicity then we have to ask why we don't have simplicity modules in our brains.

And no, I'm not gonna "experiment" with these highly astonishing beasts. I know how Archimedes was killed.
Ethelred
not rated yet Jul 16, 2010
I am curious.

Why are you worried about a Roman soldier killing you for not following orders after you help hold up their siege of Syracuse for years?

I just don't get the connection with Archimedes and fruit flies. Heck he wasn't even killed for designing war machines for Syracuse. He was killed for not jumping when a conquering soldier said jump.

Perhaps you meant someone else. Perhaps Socrates.

Flies do have fast brains. I am pretty sure I know why. Same reason we do, only since we live longer and are bigger we don't need speed above all else, couldn't anyway as our brains are two large.

We don't have system clocks. Each cell does things as fast as they can. Thus the cells that MUST have more speed than system, as a total, can handle, may do so. Some people are working on systems like that. Asynchronous computing will be the future. In the future.

Ethelred
Skeptic_Heretic
not rated yet Jul 16, 2010
We don't have system clocks.
Actually we do have system clocks. Everyone has a natural rythym that corresponds to the flow of bioelectric energy through your nerve cells.
HaveYouConsidered
5 / 5 (3) Jul 16, 2010
I made the very basic point above that those who believe in an intelligent designer need to explain where and how the designer came into existence.

There is no explanatory power in assuming the existence of something even more complex than the thing one is claiming to explain by invoking such a grandiose designer.

I still await their answer. Emotions seem to be getting in the way of rational thinking, yet again. Hoping for a life after death and feeling better by believing in a god does not make these concepts true, nor is there truthfulness established simply because many other people feel the same way, without evidence.
HaveYouConsidered
5 / 5 (2) Jul 16, 2010
For those who believe in an intelligent designer yet are open to studying scientific thought, reasoning and evidence I suggest one good starting point is Stuart Kaufman's book, "At Home in the Universe" in which the spontaneous rise of complexity is explained quite well to a lay readership. No designer needed.
Skeptic_Heretic
5 / 5 (4) Jul 16, 2010
HYC, the origin and reason for the belief in God or many gods is simple fear. When we were silly primates left in a deforrested land due to climate change we started dying rapidly to predation. Predators were stronger, faster, had better senses and were hungry for us (among other things). So fear was naturally selected for. In order for instincts, like fear, to survive in an organism, they only need to work, when they NEED to work. So those who were more fearful had higher survival rates. Being afraid of a monster in a shadow will keep you aware of the danger of that monster. Assuming there's a monster in every shadow prevents a lucky one from catching you off guard.

Now we've evolved to a point where we have some control over these sense, but, some of us can't rationally defeat our fears of the unknown as it is such a strong survival mechanism. Effectively belief is a way for the weak willed to remain functional.
254000
5 / 5 (1) Jul 19, 2010
Well, ignoring the tangent of this religion vs. evolution hash, I just thought I'd share a funny note:
A fly landed on my computer screen as I was reading this story (honestly)...and I was pleasantly amused as I thought about the 100k neurons that it was using to not only fly, but also to make me laugh.
Ethelred
not rated yet Jul 19, 2010
Actually we do have system clocks. Everyone has a natural rythym that corresponds to the flow of bioelectric energy through your nerve cells.


Multiple clocks actually and the nerve cells still work pretty much at their own rate unlike the PC I am typing on that has a 2.8GH clock that the CPU follows tick by tock. The frequencies of the brain, human anyway, are many orders of magnitude slower.

Ethelred
baudrunner
5 / 5 (2) Jul 19, 2010
If anything, the very existence of a living creature that optimizes efficiency in such a compact package which we know to have evolved over billions of years and countless more generations than the so-called "higher" life forms, is the quintessential case for evolution.
Bog_Mire
not rated yet Jul 21, 2010
HYC, the origin and reason for the belief in God or many gods is simple fear. When we were silly primates left in a deforrested land due to climate change we started dying rapidly to predation. Predators were stronger, faster, had better senses and were hungry for us (among other things). So fear was naturally selected for. In order for instincts, like fear, to survive in an organism, they only need to work, when they NEED to work. So those who were more fearful had higher survival rates. Being afraid of a monster in a shadow will keep you aware of the danger of that monster. Assuming there's a monster in every shadow prevents a lucky one from catching you off guard.

nice story SH, but I think you lost the plot there. Where is the relevance to humanities belief in a god?
I agree with your premise, but you failed to explain the fear-of-monsters/evolution of idol worship connection in full.

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