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In Brief
- The human brain lacks conspicuous characteristics—such as relative or absolute size—that might account for humans’ superior intellect.
- Researchers have found some clues to humanity’s aptitude on a smaller scale, such as more neurons in our brain’s outermost layer.
- Human intelligence may be best likened to an upgrade of the cognitive capacities of nonhuman primates rather than an exceptionally advanced form of cognition.
As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns. Only humans can perform such intellectual feats, presumably because we are smarter than all other animal species—at least by our own definition of intelligence.
Of course, intelligence must emerge from the workings of the three-pound mass of wetware packed inside our skulls. Thus, researchers have tried to identify unique features of the human brain that could account for our superior intellectual abilities. But, anatomically, the human brain is very similar to that of other primates because humans and chimpanzees share an ancestor that walked the earth less than seven million years ago.
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Add CommentRelative intelligence has always been a favorite topic of mine. I don't believe brain mass to body weight ratios are relevant. I firmly believe that the level of intelligence is controlled by four factors: first the number of neurons. More neurons equal more storage/processing capacity. Second the number of connections between neurons. Third: The ability to form complex sounds for speech (I think this is where the apes fall short) speech enables the formation of abstract thought and may even be required to form complex thoughts. Most importantly speech enables the transmission of these thoughts to others so that you can learn without having to work out each step of every problem for yourself. In our own history we can see how slow human civilization was to develop before reading became widespread. Once information could be saved and passed on, especially on a large scale our civilization, the physical manifestationof the intelligence of our species exploded. Learning actually increases the brains level of complexity. The number of neurons and connections are related to the amount of learning an organism experiences. I think that the apes are critically limited by their inability to form complex speech. They cannot form complex thoughts in form of an inner dialogue and may also simply lack the critical number of neuron/connections. I am much more interested in cetaceans who have a number of cortical neurons close to that of humans. They already exhibit what may be a complex language. I would like to see what would happen if a dolphin is trained at the earliest possible age in a language that both dolphins and humans could speak. Perhaps something like Morse code, which humans can tongue-click, and dolphins would have no trouble imitating. Early training is essential. In many of the articles I have read the brain will form (or fail to form) connections, even complete structures, based on stimulus (or lack there of). So train the infant/child dolphin to speak. Give it the same sort of learning toys human children have, the same intensive learning program a human child goes though.Provide multimedia instruction (or simple entertainment as many children learn this way) by piping in sound (adjusted for hearing range) and projecting video against a screen adhered to the tank wall. Provide them with a keyboard, not a physical keyboard, use one where each key is a tone so they would sing to control the device. In a long range study put those from the first group with the newborns to see if they pass on what they
Reply | Report Abuse | Link to thisRelative intelligence has always been a favorite topic of mine. I don't believe brain mass to body weight ratios are relevant. I firmly believe that the level of intelligence is controlled by four factors: first the number of neurons. More neurons equal more storage/processing capacity. Second the number of connections between neurons. Third: The ability to form complex sounds for speech (I think this is where the apes fall short) speech enables the formation of abstract thought and may even be required to form complex thoughts. Most importantly speech enables the transmission of these thoughts to others so that you can learn without having to work out each step of every problem for yourself. In our own history we can see how slow human civilization was to develop before reading became widespread. Once information could be saved and passed on, especially on a large scale our civilization, the physical manifestationof the intelligence of our species exploded. Learning actually increases the brains level of complexity. The number of neurons and connections are related to the amount of learning an organism experiences. I think that the apes are critically limited by their inability to form complex speech. They cannot form complex thoughts in form of an inner dialogue and may also simply lack the critical number of neuron/connections. I am much more interested in cetaceans who have a number of cortical neurons close to that of humans. They already exhibit what may be a complex language. I would like to see what would happen if a dolphin is trained at the earliest possible age in a language that both dolphins and humans could speak. Perhaps something like Morse code, which humans can tongue-click, and dolphins would have no trouble imitating. Early training is essential. In many of the articles I have read the brain will form (or fail to form) connections, even complete structures, based on stimulus (or lack there of). So train the infant/child dolphin to speak. Give it the same sort of learning toys human children have, the same intensive learning program a human child goes though.Provide multimedia instruction (or simple entertainment as many children learn this way) by piping in sound (adjusted for hearing range) and projecting video against a screen adhered to the tank wall. Provide them with a keyboard, not a physical keyboard, use one where each key is a tone so they would “sing” to control the device. In a long range study put those from the first group with the newborns to see if they pass on what they
Reply | Report Abuse | Link to thisCome on!
Reply | Report Abuse | Link to this“Accordingly, the human brain contains no highly conspicuous characteristics that might account for the species’ cleverness. For instance, scientists have failed to find a correlation between absolute or relative brain size and acumen among humans and other animal species.”
So, I have two computers, both in enclosures with the same volume, and the article wants to imply that they should have the same computing power? Poor assumption. On the bright side, the article also details why it is a bad assumption.
Two computers, same physical volume, one has a much more efficient I/O interface:
“Neither have they been able to discern a parallel between wits and the size or existence of specific regions of the brain, excepting perhaps Broca’s area, which governs speech.”
Two computers, same physical volume, one has a much more RAM:
“We have more neurons in our brain’s cerebral cortex (its outermost layer) than other mammals do.”
Two computers, same physical volume, one has a faster processor:
“The insulation around nerves in the human brain is also thicker than that of other species, enabling the nerves to conduct signals more rapidly.”
So, if I compare two computing machines occupying the same physical volume, but one of them possesses a better I/O interface, more RAM and a faster processor, should I be surprised that, that one has more capabilities?
Please excuse the snark, but it seems like a “no-brainer” to me.
Broca's area does all sorts of other things apart from language. In monkeys this region is associated with complex hand movements - as it is in humans performing 3-D rotational tasks....
Reply | Report Abuse | Link to thisNote also that glial cells are more complex in human brain than in other brains; this little appreciated observation may prove to be very important in understanding differences in plasticity and function in the human brain?
The organization of the parts of the central nervous system (brain and spinal cord) inclusive of the cerebrum (frontal, parietal, occipital, and temporaal lobes), the cerebellum and the brain stem and peripheral nervous system help differentiate the human brain from others because the the more effecient organization of the same promulgates a significantly better utelization and control of available intellectual resources both abstract and functional.
Reply | Report Abuse | Link to thisJeff Hawkins book "On Intelligence", as well as many other sources, claim the neocortex has more layers in the human than other specie at 6. An obvious difference correlating to intelligence, seems to me. The layers are not stacked one over the other but in columns. I see no mention of this in the article. I'll look again.
Reply | Report Abuse | Link to thistrying again. Jeff Hawkins' "ON INTELLIGENCE" and other sources, claim the neocortex has more layers in the human than other specie at 6. An obvious difference? Seem so to me. The layers are not on top of one another but in columns and micro-columns. Why was this not noted in the article?
Reply | Report Abuse | Link to thisTully -- I think you are missing some key information. We have mapped cranial development in all near-human/primate species. Therefore, when making our comparisons, we are using using these known quantities as a basis from which to measure similarities in the physical makeup and functional characteristics of human brains, perchance to discover key differences that might help explain the greater human intellect.. Computer box analogies are non sequitur here.
Reply | Report Abuse | Link to thisThis human machine is designed by supreme intelligence much superor
Reply | Report Abuse | Link to thisto the so called silicon machines.... ie ...Computers.
Nageswar,
Reply | Report Abuse | Link to thisThe same "supreme intelligence" that neglected to provide you with a spellcheck function?
To properly account for human intelligence it is necessary to understand that the genetically determined brain structure & culture are interrelated.
Reply | Report Abuse | Link to thisHow intelligent would a human being be, who had been raised in a chimpansee tribe? Probably not much more intelligent than other members of tribe & far less able to cope with their environment.
What makes the difference is symbolic language which makes significant cultural transmission feasible. By that I mean horizontal transmission with contemporaries & vertical transmission from past generations. As human groups expanded in size, as writing permited enhanced transmission, this speeded up. Writing led o printing, to the telegraph, the telephone, radio, TV & the internet.
Much of this process was furthered by the development up upright walking, freeing the hands for tool use. This made communicating much more important. Brain development furthered linguistic ability & linguistic ability furthered the language module of the brain. This resulted in more offsprings for an individual who functioned better in that manner, entirely in accord with modern evolutionary theory.
Of what great survival advantage would symbolic language be to a whate or an elephant?
This process is currently advancing exponentially . Given our rapidly increasing control of our own genetics it will either lead to a vastly more intelligent humanity, or we may destroy ourselves and much of other species in the process
A thought-provoking essay... which I always enjoy. That animals in general and primates, elephants and cetaceans are "intelligent" should be a surprise to no one capable of clear thinking. It seems only the religiously indoctrinated fail to see the blatantly obvious evolutionary basis for our human abilities (maladaptions as well).
Reply | Report Abuse | Link to thisI have absolutely no doubt that the neural correlates of consciousness will be fully established within my lifetime. It's not like there could be another explanation... or that the supernatural (e.g. soul) will be somehow intervening on our remarkablely evolved brains.
Not being an expert in the brain organization of other species, it seems to me that the way our brains are specialized (left versus right hemispheres) with the corpus callosum and other interhemispheric connections... along with the factors mentioned in the article and comments above... make our anatomic neural network sufficient for concious, self-reflective thought. I also agree with the commentor regarding the vital role of speech in abstract thought, since reason, like our "private" thought life and our very sense of "self" in basically a narrative.
ONCE AGAIN, the guiding principle is that humans are A PART OF NATURE... not apart from nature.
Call the unfathomable Natural World "god"... or the Cosmos, it matters not. When the bulk of humanity accepts that profound reality, determined from the very "singularity" of timespace that has inexorably evoloved to include our tiny, transient, blue-dot of the universe and humankind... we will then, have truly become more than intelligent as a specie... will will have reclaimed the wisdom of the ancients. Celebrate it!
As I commented on High-Aptitude Minds, in this article there is no explanation to size of Corpus Callosum compared to size of the brain.
Reply | Report Abuse | Link to thisThis bridge will account for the velocity and symmetry of the communication between both hemispheres. It is well known that in adults musicians and children that practice music for two yeras there is a 25% increase in CC.
Js. Gilberto
Mark Twain, on hearing that the New York Times had carried his obituary, is reported to have said: "The reports of my death are somewhat exaggerated" (or words to that effect..
Reply | Report Abuse | Link to thisIn just that fashion I fear that reports of this faculty of "intelligence" amongst us humans have been somewhat exaggerated. Evidence: examine GW Bush and his eight years of 'leadership' of the USA (the world's sole superpower).
GSC
Neither have they been able to discern a parallel between wits and the size or existence of specific regions of the brain, excepting perhaps Brocas area, which governs speech.
Reply | Report Abuse | Link to this"For instance, scientists have failed to find a correlation between absolute or relative brain size and acumen among humans and other animal species.
Both of these are not true. Take a look at the primary literature. In addition, Sciam.com just published another article stating the opposite.
For instance, relative brain sizes in specific regions such as the parietal lobe and cingulate have been shown to be bigger in more intelligent people. An in general, bigger brains show some correlation with more intelligence in humans and brain size relative to body mass is also a good starting point for a measure of intelligence in the animal kingdom.
One of the most important reason for the human capabilities is the training that the young human receives by living in an social entity of family or tribe. there they learn both language, manual and social skills. As has been proven in the case of "lost" children who grew up without such a group, the language skills have to be learned at an very young age and the cummunication by it is of major importance in the development of the brain.
Reply | Report Abuse | Link to thisOne of the most important reason for the human capabilities is the training that the young human receives by living in an social entity of family or tribe. there they learn both language, manual and social skills. As has been proven in the case of "lost" children who grew up without such a group, the language skills have to be learned at an very young age and the cummunication by it is of major importance in the development of the brain.
Reply | Report Abuse | Link to thiswhere are the graphics that are in the print version of this article??
Reply | Report Abuse | Link to thiswhere are the graphics seen in the print version of this article?
Reply | Report Abuse | Link to thiswho knew that hearing was more important than sight??
Reply | Report Abuse | Link to thisIt has always seemed to me that intelligence arises from the shared mind and rarely, if ever from a human mind raised in isolation. Because these cases are so rare this is difficult to quantify or even qualify, but it may be that development of a sufficiently complex language is the ONLY path to intelligence, rather than the reverse. The human brain, with no means of super-linking itself to the collective, may be incapable of obvious intelligence, just like the animals we study with similar brain structures.
Reply | Report Abuse | Link to thisWhat if there was an intelligence (another animal, an alien?) that used a communication system that we were unprepared to decode but that worked as well for them and was as complex as ours. Would either intelligence be able to progress past a 3-year-old understanding of the other species' language? I admit that I am having trouble even imagining how that other communication would be passed as we seem to be able to process language with 3 of our senses, and have little conscious control over the smells or tastes we create with our bodies. I suppose a complex pheromone based language would befuddle us. To answer my own question, I suspect that the answer would be no.
Reply | Report Abuse | Link to thisAs origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw problem sovling ability (that is present in so many animals) has been boosted in us. with memes (language, "sharing solutions", which in turns favors more abstract thinking and complex solutions) we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking and exchanging solutions). read about it.
Reply | Report Abuse | Link to thisAs origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw problem sovling ability (that is present in so many animals) has been boosted in us. with memes (language, "sharing solutions", which in turns favors more abstract thinking and complex solutions) we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking (what jeff hawmins ackowledges the neo cortex layers are made for) and exchanging solutions(broca area and language)). read about it. even though I think it's by far the most comprehensive theory on human brain evolution, it's the right piece of puzzle, the right way to see it, it is still controversial and not well known.
Reply | Report Abuse | Link to thisAs origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw "problem-sovling ability" (that is present in so many animals) has been boosted in us, only because of memes(language, "sharing solutions", which in turns favors more abstract thinking and complex solutions). with memes we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking (what jeff hawkins ackowledges the neo cortex layers are made for) and exchanging solutions(broca area and language)). read about it. even though I think it's by far the most comprehensive theory on human brain evolution, it's the right piece of puzzle, the right way to see it, it is still controversial and not well known.
Reply | Report Abuse | Link to thisso yeah the key is definitely language. intelligence is in "information". and with sharing information, we get more "problem solving ability" (we today of course reach levels that are inconceivable without culture, language, sharing info) for the same (nutrition-costly) brain size. so basically language is a trick. other species do have problem solving abilities, but with language we are just at a complete other level. that's it. it's pretty evident afterall some would say.
As origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw "problem-sovling ability" (that is present in so many animals) has been boosted in us, only because of memes(language, "sharing solutions", which in turns favors more abstract thinking and complex solutions). with memes we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking (what jeff hawkins ackowledges the neo cortex layers are made for) and exchanging solutions(broca area and language)). read about it. even though I think it's by far the most comprehensive theory on human brain evolution, it's the right piece of puzzle, the right way to see it, it is still controversial and not well known.
Reply | Report Abuse | Link to thisso yeah the key is definitely language. intelligence is in "information". and with sharing information, we get more "problem solving ability" (we today of course reach levels that are inconceivable without culture, language, sharing info) for the same (nutrition-costly) brain size. so basically language is a trick. other species do have problem solving abilities, but with language we are just at a complete other level. that's it. it's pretty evident afterall some would say.
As origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw "problem-sovling ability" (that is present in so many animals) has been boosted in us, only because of memes(language, "sharing solutions", which in turns favors more abstract thinking and complex solutions). with memes we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking (what jeff hawkins ackowledges the neo cortex layers are made for) and exchanging solutions(broca area and language)). read about it. even though I think it's by far the most comprehensive theory on human brain evolution, it's the right piece of puzzle, the right way to see it, it is still controversial and not well known.
Reply | Report Abuse | Link to thisso yeah the key is definitely language. intelligence is in "information". and with sharing information, we get more "problem solving ability" (we today of course reach levels that are inconceivable without culture, language, sharing info) for the same (nutrition-costly) brain size. so basically language is a trick. other species do have problem solving abilities, but with language we are just at a complete other level. that's it. it's pretty evident afterall some would say.
As origami pointed out, (very good comment I think), it's all about language (and writing). I would go even one step further and say that it's all about memes, actually (see susan blackmore, the meme machine). our brain has been slightly modified/ expanded (from apes) to host memes better. and the raw "problem-sovling ability" (that is present in so many animals) has been boosted in us, only because of memes(language, "sharing solutions", which in turns favors more abstract thinking and complex solutions). with memes we act more intelligent. intelligence can be defined by some as "being able to find more solutions" but can also be "having solutions". memes, anyway, increase both. I think it's a really nice theory that explains human brain evolution very well (brain optimized for stocking (what jeff hawkins ackowledges the neo cortex layers are made for) and exchanging solutions(broca area and language)). read about it. even though I think it's by far the most comprehensive theory on human brain evolution, it's the right piece of puzzle, the right way to see it, it is still controversial and not well known.
Reply | Report Abuse | Link to thisso yeah the key is definitely language. intelligence is in "information". and with sharing information, we get more "problem solving ability" (we today of course reach levels that are inconceivable without culture, language, sharing info) for the same (nutrition-costly) brain size. so basically language is a trick. other species do have problem solving abilities, but with language we are just at a complete other level. that's it. it's pretty evident afterall some would say.
"As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns."
Reply | Report Abuse | Link to thisThis is a very unscientific statement, based on belief, not knowledge or evidence. The whole "humans are smarter than animals" certitude looks very weakly substantiated to me, based upon what WE understand with OUR language, what WE express - OUR music - or what WE are able to achieve - toolmaking, building etc. The truth is, nobody has a clue what happens in a big whale's brain - just as an example - and perhaps these mammals have access to a kind of information, scientific laws etc. which we humans are still struggling to understand. Marc Hauser, in his recent article in Scientific American, states, recklessly to my opinion, that "humans are smarter than creatures whose brains are larger than ours". Smarter, here, actually means different. This seems to me like a very narrow and anthropocentrist take on intelligence. If we use as a sign of intelligence the ability to predict and escape a natural catastrophe such as a tsunami, humans are among the most poorly equipped species on earth as the recent Asian tsunami showed. This type of article is the belief-oriented, pattern-seeking, rich on seemingly obvious "truths" but poor on evidence kind that scientific progress has discarded time and time again and which Michael Shermer regularly and brilliantly criticizes in his Skeptic" articles.
Very clever
Reply | Report Abuse | Link to thisVery true. Who are we to determine the meaning of "intelligence"? "As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns." Why does a dolphin nedd to speak in rymes? When it can perform tricks, why does a dog need to compose music when it can lead the blind. We fail to acknowledge the accomplishments of the other mammels that occupy this world with us. Granted some animals appear very unintelligent but isnt their menatally retarded humans? We cannot compare the intelligence of one to a species.
Reply | Report Abuse | Link to thisUpdate some science comprehensions:
Reply | Report Abuse | Link to thisSee way back…
http://universe-life.com/2006/03/23/seed-of-human-chimp-genomes-diversity-2/
Dov Henis (comments from 22nd century)
http://universe-life.com/2012/02/03/universe-energy-mass-life-compilation/
If an octopus unscrews the lid to a jar to get to food inside the jar, isn't it solving an 'equation' with two unknowns?
Reply | Report Abuse | Link to thisWhat is this object?
Why can't I reach that food?
Is this part of the object (the metal lid) different from the rest (containing the visible food)?
How did the food get in there?
How can the lid be removed from the jar?
In fact, that's six initial unknowns.
:)