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How tiny wasps cope with being smaller than amoebas

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Re: How tiny wasps cope with being smaller than amoebas

#61

Earlier quoted context omitted.

7,400 seems very capable of being simulated. In fact, that's a small enough number that I'll bet you could map those connections out by hand with some type of microscope. To someone more knowledgeable in this subset of biology, is this possible?

It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior (relative timings of post and pre-synaptic activations), complex chemistry in the cell as well as the in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems (or even more than…

Jefe: "It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior, complex chemistry in the cell as well as in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems, these computing units take precise roles, part due to the developmental process, part due to later stage learning. "

El Guapo: "Would you say, senor, that I have a plethora of signals in each computing unit? And I just would like to know if you know what a plethora is. I would not like to think that a person would tell someone he has a plethora, and then find out that that person has no idea what it means to have a plethora."

Jefe: "Forgive me, El Guapo. I know that I, Jefe, do not have your superior intellect and education. But could it be that once again, you are angry at something else, and are looking to take it out on me?"

http://www.youtube.com/watch?v=-mTUmczVdik

"But in the end, the machinery is precise, and simulating it requires understanding all of it."

Sorry to pick at you for this, but how can you be certain of the many claims you've made here? How do you know that intelligence cannot be implemented in a mechanism simpler than the biological hardware implementation or simulations thereof?

Re: How tiny wasps cope with being smaller than amoebas

#62

Earlier quoted context omitted.

It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior (relative timings of post and pre-synaptic activations), complex chemistry in the cell as well as the in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems (or even more than…

Jefe: "It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior, complex chemistry in the cell as well as in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems, these computing units take precise roles, part due to the developmental…

(Did I misuse "plethora"? English is not my first language, sorry if I shouldn't use plethora)

> How do you know that intelligence cannot be implemented in a mechanism simpler than the biological hardware implementation or simulations thereof?

I don't know if intelligence cannot be implemented in a simpler way (I certainly hope it can), I am concerned here about understanding the biological implementation of intelligence. I say that simulations are useful because the models that we may make of the emergence of the mechanisms of intelligence in networks of neurons would be very hard to understand without being implemented and simulated.

However, if you are interested in the artificial implementation of the intelligent behavior of some organisms, you could maybe still benefit from understanding how this intelligent behavior arises in these organisms, and take inspiration from these mechanisms.

> Sorry to pick at you for this, but how can you be certain of the many claims you've made here?

I didn't make revolutionary claims regarding the functioning of biological neural networks. The fact that neurons are sensitive to relative spike timing is evident in mechanisms like spike timing dependent plasticity (http://www.scholarpedia.org/article/Spike-timing_dependent_p...). The "complex chemistry" that I mention is behind cognition is evident if you open any neurology book, for instance Principles of Neural Science by Kandel.

Then, I say that simulation (and in particular simulation of development as well as learning) is the right road to understanding biological neural systems, but I took care to mention that it is what I believe, not what I know.

Re: How tiny wasps cope with being smaller than amoebas

#63
post #10

What are the major technical barriers before we can identify the input and output channels to this insect's brain and start iterating through all possible input values, recording the corresponding output values? And once we can do that, could we use that data to fly a virtual insect around a virtual world?

Honest newbie question: Why would we even want to do that? Exclusively for academic medical purposes? (ie learning how our body works) It seems to me, that since evolution is highly imperfect, that trying to mimic living beings, might not be the best idea. While we do mimic them a lot, mostly it seems to be for learning until we can do better. But in this case. Since it's so expensive and not viable to mimic them pro…

Because Science, man.

You don't do things in science because they are practical (you just write that on the grant applications), in fact you do many things largely because they are impractical.

It's about wonder and lust for knowledge and all that. It just so happens that the theoretical ground work for all technology piggy backed on this motivation.

Re: How tiny wasps cope with being smaller than amoebas

#64
post #44
post #31

Wow: with only 7,400 neurons (compared to 340,000 for the common housefly and 850,000 for honeybees), this wasp can somehow fly, search for food, find the right places to lay its eggs, etc. That ridiculously tiny neural network is one freakingly efficient computing device!

"this wasp can somehow [...] find the right places to lay its eggs" I bet this wasp is playing the "you do not need eyes to hit bullseye if you throw a million darts" game. It is sufficien t if some of these wasps, almost by accident, happen to lay their eggs in the right place.

It costs resources to produce an egg. There has to be some processing going on.

Re: How tiny wasps cope with being smaller than amoebas

#65
post #57

Earlier quoted context omitted.

How do you know when you've simulated a worm's brain correctly? I mean, they don't actually do much, do they?

Worms ( C. elegans specifically) have specific well-documented responses to certain stimuli. You can apply those same stimuli to your simulated worm and see if it responds like a typical real worm.

Sort of like a wormy unit test. Strange thought!

Re: How tiny wasps cope with being smaller than amoebas

#66

Earlier quoted context omitted.

Jefe: "It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior, complex chemistry in the cell as well as in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems, these computing units take precise roles, part due to the developmental…

(Did I misuse "plethora"? English is not my first language, sorry if I shouldn't use plethora) > How do you know that intelligence cannot be implemented in a mechanism simpler than the biological hardware implementation or simulations thereof? I don't know if intelligence cannot be implemented in a simpler way (I certainly hope it can), I am concerned here about understanding the biological implementation of intellig…

Your use of plethora was completely right. For some reason giardini thinks it is a very obscure and "intellectual" word but I disagree. In Google's English corpus it is used about 1/3 as often as the word "neuron". http://books.google.com/ngrams/graph?content=plethora%2Cneur...

Re: How tiny wasps cope with being smaller than amoebas

#67

Earlier quoted context omitted.

It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior (relative timings of post and pre-synaptic activations), complex chemistry in the cell as well as the in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems (or even more than…

Jefe: "It is possible, but the neurons are actually complex computing units that take a plethora of signals into account: subtle temporal behavior, complex chemistry in the cell as well as in the synaptic cleft, and many more less understood things. Secondly, as you can imagine, the connectivity is far from random. Like in larger nervous systems, these computing units take precise roles, part due to the developmental…

how can you be certain of the many claims you've made here?

It says most of this in the article. e.g. "It turns out that social behavior in the worm is controlled by a pair of neurons called RMG. The two RMG neurons receive input from various sensory neurons that detect the several environmental cues that make worms aggregate. RMG integrates this information and sends signals to the worm’s muscles." You have to understand genetics, smells, sensors, neurons, and muscles before you can explain why worms in nature tend to be together, but worms in the lab stay by themselves.

Re: How tiny wasps cope with being smaller than amoebas

#68
post #66

Earlier quoted context omitted.

(Did I misuse "plethora"? English is not my first language, sorry if I shouldn't use plethora) > How do you know that intelligence cannot be implemented in a mechanism simpler than the biological hardware implementation or simulations thereof? I don't know if intelligence cannot be implemented in a simpler way (I certainly hope it can), I am concerned here about understanding the biological implementation of intellig…

Your use of plethora was completely right. For some reason giardini thinks it is a very obscure and "intellectual" word but I disagree. In Google's English corpus it is used about 1/3 as often as the word "neuron". http://books.google.com/ngrams/graph?content=plethora%2Cneur...

I see, thanks. And that's a really nice tool, this n-gram viewer. Thanks for the link!

Re: How tiny wasps cope with being smaller than amoebas

#69
post #26

Earlier quoted context omitted.

No, an ostrich cell really is a single cell. http://en.wikipedia.org/wiki/Egg_yolk

So are you saying the whole yolk divides in half continually to form the embryo? Is there a cell membrane around the yolk?

> So are you saying the whole yolk divides in half continually to form the embryo?

No, the yolk does not "divide", the developing embryo feeds on its content.

Re: How tiny wasps cope with being smaller than amoebas

#70

Earlier quoted context omitted.

Worms ( C. elegans specifically) have specific well-documented responses to certain stimuli. You can apply those same stimuli to your simulated worm and see if it responds like a typical real worm.

Sort of like a wormy unit test. Strange thought!

Actually that's pretty much what they are. There us a whole battery of stimulus stimulus-response tests that are essentially used as a regression test suite to figure out what deleterious (or even beneficial) effect a given mutation has. Of course these "tests" must be manually carried out by researchers on live worms.
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