Bigger not necessarily better, when it comes to brains

Nov 17, 2009

(PhysOrg.com) -- Tiny insects could be as intelligent as much bigger animals, despite only having a brain the size of a pinhead, say scientists at Queen Mary, University of London.

"Animals with bigger brains are not necessarily more intelligent," according to Lars Chittka, Professor of Sensory and Behavioural Ecology at Queen Mary's Research Centre for Psychology and University of Cambridge colleague, Jeremy Niven. This begs the important question: what are they for?

Research repeatedly shows how insects are capable of some intelligent behaviours scientists previously thought was unique to larger animals. Honeybees, for example, can count, categorise similar objects like dogs or human faces, understand 'same' and 'different', and differentiate between shapes that are symmetrical and asymmetrical.

"We know that body size is the single best way to predict an animal's brain size," explains Chittka, writing in the journal , today. "However, contrary to popular belief, we can't say that brain size predicts their capacity for intelligent behaviour."

Differences in brain size between animals is extreme: a whale's brain can weigh up to 9 kg (with over 200 billion nerve cells), and human brains vary between 1.25 kg and 1.45 kg (with an estimated 85 billion nerve cells). A honeybee's brain weighs only 1 milligram and contains fewer than a million nerve cells.

While some increases in do affect an animal's capability for intelligent behaviour, many size differences only exist in a specific brain region. This is often seen in animals with highly developed senses (like sight or hearing) or an ability to make very precise movements. The size increase allows the brain to function in greater detail, finer resolution, higher sensitivity or greater precision: in other words, more of the same.

Research suggests that bigger may need bigger brains simply because there is more to control - for example they need to move bigger muscles and therefore need more and bigger nerves to move them.

Chittka says: "In bigger brains we often don't find more complexity, just an endless repetition of the same neural circuits over and over. This might add detail to remembered images or sounds, but not add any degree of complexity. To use a computer analogy, bigger brains might in many cases be bigger hard drives, not necessarily better processors."

This must mean that much 'advanced' thinking can actually be done with very limited neuron numbers. Computer modelling shows that even consciousness can be generated with very small neural circuits, which could in theory easily fit into an insect .

In fact, the models suggest that counting could be achieved with only a few hundred and only a few thousand could be enough to generate consciousness. Engineers hope that this kind of research will lead to smarter computing with the ability to recognise facial expressions and emotions.

More information: www.cell.com/current-biology/f… 0960-9822(09)01597-8

Source: Queen Mary, University of London (news : web)

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axemaster
not rated yet Nov 17, 2009
""We know that body size is the single best way to predict an animal's brain size," explains Chittka"..."The size increase allows the brain to function in greater detail, finer resolution, higher sensitivity or greater precision"

Yes, it is indeed reasonable to assume that since a larger animal has more "channels" of sensor inputs, it would need a proportionally, perhaps even exponentially larger brain to process those inputs.
galoot
5 / 5 (1) Nov 17, 2009
"Computer modelling shows that even consciousness can be generated with very small neural circuits..."

Thats big news. I dont think its been modelled or else it would be already be done and hello HAL.

Perhaps the definition of "consciousness" should be included to justify this astonishing claim.
SincerelyTwo
4.3 / 5 (3) Nov 17, 2009
Instead of making long assumptions about what you *think consciousness is, stop and think about what makes you think you're conscious. You can consider yourself, within yourself, so your mind is a machine capable of recursive reasoning, and self-correcting effects. Consider also the nature of complexity, how simple and nearly* identical systems over long periods of time can grow to be distinct, no longer recognizable by its instantiation.

Given many simple, specific, functionality, and years of time to propagate / store+consume information, it's perfectly reasonable to argue that the meaning* of our interpretations of 'all the' complexity we think we see is truly an illusion.

What is, is exactly what is. It must all tie back in to the fabric of reality, otherwise it's irrational and nonsense. While it might make you feel emotionally at ease to think that the answer is there's just a God to answer for all the complexity, the truth is quite simple in nature. At least that's my opinion.
somnum
5 / 5 (1) Nov 18, 2009
When did galoot say anything about God?
He's absolutely right though. Whether or not recursive reasoning and self correcting effects are all that is needed for consciousness (sounds ludicrous to me personally but hey, you never know) or whether they are facets of consciousness is a little irrelevant; the article claims that consciousness can be generated with very small neural circuits, and that is certainly conjecture.
gwrede
1 / 5 (4) Nov 18, 2009
I'm sorry to tell, but there is no such thing as consciousness.

It's simply an illusion that the person has about himself. I can look at myself in a mirror, or think that I exist, "therefore I'm a conscious being".

No matter how big a computer is mounted on a humanoid robot, people still would not say it's conscious. Instead, they'd say "it simply follows the algorithms programmed into it". Well, so do people, too.

Things were easier in the old days, when humans only were considered conscious (only man had a soul). Killing cattle was what we did, without any thoughts about consciousness. Today many are vegetarians, and you can't kill an animal in public. Tomorrow we can't kill rats, soon not even mosquitoes.
Sancho
1 / 5 (2) Nov 18, 2009
The work of Dr Ian Stevenson among many others seems to validate the idea of reincarnation. If indeed something "personal" survives death, then neural circuits have nothing to do with consciousness. To use Chittka's analogy, the brain is akin to a PC (with webcam & mike) --- the processing is done in this world, but the keyboardist moves on to another machine when the boards burn out. (Let the flaming begin.)

Ethelred
4.5 / 5 (2) Nov 18, 2009
I'm sorry to tell, but there is no such thing as consciousness.
This is just an attempt to redefine the word 'consciousness' to the point of meaninglessness.

If an entity perceives itself as a thinking being separate from other beings than that entity is self-conscious. More to the point a being that is aware of its own thinking is self-conscious. Calling this an illusion is self deception. Something I suspect that is difficult for a entity that is not self-conscious.

In other words you are conning yourself which is a clear indication that you are self-conscious.

Ethelred
Ethelred
4.5 / 5 (2) Nov 18, 2009
If indeed something "personal" survives death, then neural circuits have nothing to do with consciousness.


Bloody big IF. The article said no such thing in any case.

Counting does not require consciousness and Chittka is just plain full of it on that point. The PC I am typing this on can count far better than I but I haven't seen it complaining that it needs a break to meditate.

That insects are capable of things MOST people don't think they can do is hardly evidence that they are self-conscious in anyway. One chemical pathway triggers another. Unless there is a path that is observing these paths and is capable of observing itself as well then I don't see any sign of self-consciousness.

Ethelred
Chromanoid
not rated yet Nov 18, 2009
http://chittkalab...ol09.pdf
the original publication. i think consciousness is an eyecatcher... in the publication consciousness is literally never mentioned.
droid001
5 / 5 (1) Nov 18, 2009
I agree with Ethelred. Can a bee to pretend? Dogs can.
What about feelings? inspiration? Just algorithms? No way
gwrede
not rated yet Nov 21, 2009
I'm sorry to tell, but there is no such thing as consciousness.
This is just an attempt to redefine the word 'consciousness' to the point of meaninglessness.


Yes, you are correct. (Which of course, came from the realization that 'consciousness' itself was an illusion, and as such, *somebody* had to point that out to the audience.)

If an entity perceives itself as a thinking being separate from other beings than [er, then?] that entity is self-conscious. More to the point, a being that is aware of its own thinking is self-conscious. Calling this an illusion is self deception. Something I suspect that is difficult for a entity that is not self-conscious.
Hmm. All is very nice, of course, but if I were to seriously challenge you, then you'd start nit-picking on the word "aware".

"In other words, you are conning yourself which is a clear indication that you are self-conscious."

Thanks, that was quite witty!

Ethelred
5 / 5 (1) Nov 23, 2009
t. (Which of course, came from the realization that 'consciousness' itself was an illusion,
Again that is merely an attempt to turn English into a meaningless collection of random sounds.
but if I were to seriously challenge you, then you'd start nit-picking on the word "aware".
The other way around. You are pretending that the words have no meaning. Basically if you were correct than you wouldn't be discussing this.

Or to put it differently you have deluded yourself that your awareness is an illusion. You MIGHT, indeed I think you most likely would be correct IF we lived in an entirely different world than we do. Newton's World.

We live in Heisenberg's World. A world of uncertainty and not a Mechanical Universe. In a purely mechanical universe you would be absolutely correct since everything would follow from the initial conditions and thus choice would be illusory.

But we don't live in that world.

Ethelred