What factors contribute to the behavior of fruit flies in featureless rooms?

[PIT2]

Insects and other animals are often seen just "as very complex robots," Brembs said, for which behavior is determined solely by reactions to the outside world. When scientists observe animals responding in different ways to the same outside cues, such variations are typically attributed "to random errors in a complex brain," he said.

Brembs and his colleagues reasoned that if fruit flies (Drosophila melanogaster) were simply reactive robots entirely determined by their environment, in completely featureless rooms they should move completely randomly. To investigate this idea, the international team of researchers glued the insects to small copper hooks in completely uniform white surroundings, a kind of visual sensory deprivation tank. These flies could still beat their wings and attempt to turn.

A plethora of increasingly sophisticated computer analyses revealed that the way the flies turned back and forth over time was far from random. Instead, there appeared to be "a function in the fly brain which evolved to generate spontaneous variations in the behavior," Sugihara said.

source: http://www.msnbc.msn.com/id/18684016/?GT1=9951

 

[Mk]

I'm still waiting for evidence that says we do have free will other than assumption. I don't see why if they moved in a pattern or if we couldn't figure out the pattern in which they moved determines or provides evidence for free will in fruit flies.

 

[Moonbear]

Flies respond to more than just visual cues, so if the only thing they controlled was the color of the room, this study is meaningless. What about sounds, pheromonal cues left by other flies in the room, other odor cues, air flow (surely the room had a ventillation system), etc.?

 

[Ivan Seeking]

It seems to me that the assumption of "random errors" is what needs proving. I assume that there is no way to support this claim?

 

[Moonbear]

It seems to me that the assumption of "random errors" is what needs proving. I assume that there is no way to support this claim?

I agree. How do you know that soemthing ISN'T randomly generated? Just because you can find a pattern in it doesn't mean there was some form of intention in the creation of that pattern.

 

[Ivan Seeking]

Barring any elegant solutions, I guess it would come down to accouting for every connection in part of the brain - the part associated with the activity observed - and determining an envelope of possible variations?

...not that I'm saying we can do this yet... can we? I have no idea what the state-of-the-art is for this level of understanding, but at least a fly brain isn't very big.

Right now, "random errors" sound a bit like an easy out and catch-all.

 

[Ivan Seeking]

I was thinking about this and was reminded of something in my own work. When someone doesn't understand the control schemes and programming used in automation, and when systems do things that they don't understand, it is common for people to assume that the system is making random errors, when in fact [barring failing components] nothing random ever happens. Everything always does exactly what the logic in the programming requires.

So when they talk about random errors in brains, where would these errors occur? Is this a matter of a synapse firing one time but failing the next? Or, perhaps a probability operating over a large number of synapses where if some percentage fail to fire then we turn left instead of right?

 

[light_bulb]

speaking of robots, sometimes they will have to make precived random movements until they can home in on their bearings. say you have a tape line used as a track and the robot gets knocked off the track, if it acts like a roomba and just makes a turn until it senses the line it will appear random, unless you know that the tape line exists, because it's unlikely it will be knocked off the tape line the exact same way again.

 

[DaveC426913]

Flies respond to more than just visual cues, so if the only thing they controlled was the color of the room, this study is meaningless. What about sounds, pheromonal cues left by other flies in the room, other odor cues, air flow (surely the room had a ventillation system), etc.?

Duh. This is science. I think it goes without saying that they put tiny little noseplugs and earplugs on them.



As far as "random errors in the brain", do they not account for the likelihood that THE element of randomness is EVOLVED? A fly that had fixed deterministic rules for navigation would die pretty quick. An evolved "random element" would be selected for.