NationStates Jolt Archive

I was reading the other thread on IQ scores and I was thinking of a few things. I'd like to know the opinions of some people on this topic. I have my own opinions but I want to see what others say.

Can a person actively do things to increase his intelligence?

Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?

Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?

I agree with the third option.
WRT the first, i don't think you can increase your innate intelligence, but you can increase your ability to learn, you can practice and improve different areas of your brain... and ultimately it may be hard to distinguish the effect of all that from an increase in intelligence...

Can a person actively do things to increase his intelligence?

Yep. Drink massively, over a prolonged time, and you can watch a person grow dumber.


Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?

All three of them. It's partly hereditary, depends partly on the amount of stimulation and the quality and amount of nutrition during the early years of childhood, and emotional aspects and components.


Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?

Ever heard of something called "EQ"? Emotional intelligence? That, and the ability to mimic and to adjust to social environment make a person smart.

also... ever read 'Brave New World'? Suggests one possible answer to question 2.

I think NS has made me smarter. I read lots here, and look up the spellings of big words and use my brain sometimes. :)

Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?

Ever heard of something called "EQ"? Emotional intelligence? That, and the ability to mimic and to adjust to social environment make a person smart.

I don't actually think "eq" is important, or that it is what makes someone "smart" in my opinion.

I don't actually think "eq" is important, or that it is what makes someone "smart" in my opinion.

Maybe that is because you have a low EQ? :D

I don't actually think "eq" is important, or that it is what makes someone "smart" in my opinion.

You think that being able to decipher other people's feelings, to read their behaviour correctly and adjust your behaviour accordingly, and thereby effectively influencing their decisions, is not smart?

Ok, it IS a matter of definition if you regard someone as smart who is a genius in one single field in life, but a complete loser in all others (computer geeks, anyone? ;) ), or if you regard someone as smart who manages to get his life together, to make the best out of every given situation and to succeed in whatever he decides to do.
I'd go for the second type of person. I've met plenty of the first type, and while they were very clever when their own special field was concerned, they were hardly smart people.

You think that being able to decipher other people's feelings, to read their behaviour correctly and adjust your behaviour accordingly, and thereby effectively influencing their decisions, is not smart?

Ok, it IS a matter of definition if you regard someone as smart who is a genius in one single field in life, but a complete loser in all others (computer geeks, anyone? ;) ), or if you regard someone as smart who manages to get his life together, to make the best out of every given situation and to succeed in whatever he decides to do.
I'd go for the second type of person. I've met plenty of the first type, and while they were very clever when their own special field was concerned, they were hardly smart people.

That's not what I think.

I think that there are dimensions to being smart. A combination of intelligence, knowledge, wisdom, and craft/cleverness, and creativity (ingenuity being included with intelligence).

Can a person actively do things to increase his intelligence?
Definitely. Reading, writing, debating...Any sort of stimulation to the brain is going to increase your thinking and cognitive abilities. IIRC, it has shown to strengthen, and in fact create new, pathways throughout your brain. Your perception is dependant on your cognitive ability and your linguistic resources. Thus improving one is going to lead to an 'increase' in intelligence.

Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?
Determined by both factors. My feeling is that we're born with an intelligence 'potential' and childhood development plays a huge role in helping us achieve that potential.

Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?
Like someone else already said, there's EQ. There's also multiple intelligences (Gardner) - everyone is better suited in some areas than others. Some are gifted at music, some in mathematics, others in languages.
There is no 'one' intelligence.

That's not what I think.

I think that there are dimensions to being smart. A combination of intelligence, knowledge, wisdom, and craft/cleverness, and creativity (ingenuity being included with intelligence).

That pretty much includes EQ...

You think that being able to decipher other people's feelings, to read their behaviour correctly and adjust your behaviour accordingly, and thereby effectively influencing their decisions, is not smart?

Autistics and Aspergians lack much of that, and yet, tend to become the best in their fields. Ever hear of the Austistic guy who learned Icelandic in a WEEK? Not to mention Einstein, Newton, Bill Gates and Satoshi Tajiri.

Autistics and Aspergians lack much of that, and yet, tend to become the best in their fields. Ever hear of the Austistic guy who learned Icelandic in a WEEK? Not to mention Einstein, Newton, Bill Gates and Satoshi Tajiri.

That's what I said. People can be extremely intelligent and sheer geniuses in their particular fields, but completely lost at other aspects of life.
Intelligence is merely part of the whole.

EQ is about the instinctual bit, and thus separate from intelligence. All that can be done instinctually by those with a high EQ, could be done better through intellectual effort by someone with a good enough intellectual capability. (though that truly requires one that is extraordinary)

Do you know what's funny? A natural genius would have a pretty low IQ according to tests. A vast majority of IQ tests rely on a "guess what the author intended" principle.
Take for example this mathematical sequence: 1 2 4 8 ?
Now what number can be the last number? a) 16 b) 100 c) 32 d) 24
The right answer in every IQ test would naturally be a).
Let's take aside the fact that numbers in any mathematical sequence can be totally unrelated and let's examine the relation between these numbers:
We have 2=2*1, 4=2*2, 8=2*4... So the relation seems to be a_n = a_(n-1) * 2 and according to this formula the next number would be 16.
Now let's take this (rather complex) equation: a_n = 2125/600*n^4 - 35.25*n^3 + 370375/3000*n^2 - 175.75*n + 85
Now according to this equation: a_1=1, a_2=2, a_3=4, a_4=8, a_5=100
Now why would not b) be the correct answer? The formula is as valid as the first one!
The answer is simple: It was the author's intention! :)

I was reading the other thread on IQ scores and I was thinking of a few things. I'd like to know the opinions of some people on this topic. I have my own opinions but I want to see what others say.

Can a person actively do things to increase his intelligence?

It is possible to enhance a variety of cognitive functions through conscious activities. It is quite possible to improve one's IQ score (which is one of the reasons IQ tests should be regarded with skepticism).


Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?

Yes. Cognitive ability is due to a combination of factors, including (but not limited to) genetics, environmental factors such as diet and upbringing, and even individual personality.

Additionally, how our "intelligence" is perceived by others has a lot to do with how we choose to express it.


Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?
If by "intelligence" you mean "IQ," then the answer is obviously "yes." Plenty of very smart people would flunk an IQ test.

Can a person actively do things to increase his intelligence?
yes

Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?
all of the above.

Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?
yes.

Do you know what's funny? A natural genius would have a pretty low IQ according to tests. A vast majority of IQ tests rely on a "guess what the author intended" principle.
Take for example this mathematical sequence: 1 2 4 8 ?
Now what number can be the last number? a) 16 b) 100 c) 32 d) 24
The right answer in every IQ test would naturally be a).
Let's take aside the fact that numbers in any mathematical sequence can be totally unrelated and let's examine the relation between these numbers:
We have 2=2*1, 4=2*2, 8=2*4... So the relation seems to be a_n = a_(n-1) * 2 and according to this formula the next number would be 16.
Now let's take this (rather complex) equation: a_n = 2125/600*n^4 - 35.25*n^3 + 370375/3000*n^2 - 175.75*n + 85
Now according to this equation: a_1=1, a_2=2, a_3=4, a_4=8, a_5=100
Now why would not b) be the correct answer? The formula is as valid as the first one!
The answer is simple: It was the author's intention! :)


On the other hand, I think being able to determine the answer the test-makers were looking for is an attribute of intelligence. I do it on tests all the time: "What answer do they want?"

As for the matter of EQ, I think it's just a different kind of smart, as has been alluded to by other posters. However, you can have people who are amazingly intelligent, but lack any kind of interpersonal skills.

Do you know what's funny? A natural genius would have a pretty low IQ according to tests. A vast majority of IQ tests rely on a "guess what the author intended" principle.

yes, that's very true, for example I gave a worksheet to my child once with the sequence

1 3 5 7

and the instruction to "finish the pattern"

she finished it a few different ways, once with odd numbers, once with prime numbers, and once with a pattern based on

"add three, add two, add two, add three, add two, add two"

all three may have been correct, it would only depend on what I intended the pattern to be.

On the other hand, I think being able to determine the answer the test-makers were looking for is an attribute of intelligence. I do it on tests all the time: "What answer do they want?"

Isn't that more like EQ than IQ then?

EQ is about the instinctual bit, and thus separate from intelligence. All that can be done instinctually by those with a high EQ, could be done better through intellectual effort by someone with a good enough intellectual capability. (though that truly requires one that is extraordinary)

I beg to differ. No amount of intelligence will ever let you gauge another persons emotions.
A lot of it is instinctive, but then again, so is intelligence. Keep in mind, intelligence is the ability to solve a new problem by thinking it over, not just applying knowledge (applying knowledge out of context would be a sign of intelligence)

yes, that's very true, for example I gave a worksheet to my child once with the sequence

1 3 5 7

and the instruction to "finish the pattern"

she finished it a few different ways, once with odd numbers, once with prime numbers, and once with a pattern based on

"add three, add two, add two, add three, add two, add two"

all three may have been correct, it would only depend on what I intended the pattern to be.

That's why I like children! They are way smarter than we are! :) Too bad people lose these ways of thinking when they grow up :( I wonder if the loss is purely natural or if it's because of social influence.

That pretty much includes EQ...

I don't see how though, wouldn't 'eq' be the measure of skill in and intuition that is applicable to interpersional relations and an understanding of empathy?

We might be using words different ways. I had this discussion with my friend and 'intelligence' has more than one meaning to him because he has a different vocabulary than I do.

So this is how I define those things:

Knowledge: Amount of information collected about a singular topic or variety of topics.
Creativity: Capacity to create new ideas.
Intelligence: Capacity to reason and interrelate ideas to find patterns. (Including ingenuity which is using novel approaches to correlate data.)
Widsom: Using or relating knowledge in a way that is most appropriate/most efficient in each instance.
Craft/cleverness: The ability to apply novel approaches (not necessarily to create them) to a variety of topic and finding 'loopholes' in information and reasoning.

That's why I like children! They are way smarter than we are! :) Too bad people lose these ways of thinking when they grow up :( I wonder if the loss is purely natural or if it's because of social influence.

Social influences. Most of my maths teachers would have told me that the prime number pattern and the adding pattern are wrong, and only the odd numbers pattern is correct. I only ever had one who was clever enough to realise that different brains see different patterns, and that one and the same mathematical problem can have more than one solution. Such teachers are few, but they make up for so much. :)

That's why I like children! They are way smarter than we are! :) Too bad people lose these ways of thinking when they grow up :( I wonder if the loss is purely natural or if it's because of social influence.

I think it is social influence that leads to a supression and eventually loss (not total in any way) of these natural abilities.

I remember having amazing reasoning skills as a child and constantly being told "that doesn't matter, stop thinking, start being practical". Fortunately I was an extremely obstinate child so I decided to continue to reason things in my own way. Eventually I did lose some of this for practicality but still retain much of it.
I'm terrible at some practical things compared to other people but when put into a new situation I am able to comprehend and learn faster than most people.
Which leads me to being competent more quickly, but generally less so in the long run. I wish I could have both but I'm happier this way as opposed to the other way. Imagine how restricted the thinking of these people must be when they're just pondering in their own minds! I would hate to just be able to think of things that exist in the here and now and how to use them. What was, what could be, and why things occur is so much more interesting than the drudgery of learning how to do certain things and having nothing to do in the mind when 'mental work' isn't being done.

Social influences. Most of my maths teachers would have told me that the prime number pattern and the adding pattern are wrong, and only the odd numbers pattern is correct. I only ever had one who was clever enough to realise that different brains see different patterns, and that one and the same mathematical problem can have more than one solution. Such teachers are few, but they make up for so much. :)

you are right, I almost did it to her too, since 1+2=3 so the "add three" is incorrect, and since 2 is a prime number so it should have been 1, 2, 3, 5, 7

but I didn't, I let it slide, you know since she is 3.

Social influences. Most of my maths teachers would have told me that the prime number pattern and the adding pattern are wrong, and only the odd numbers pattern is correct. I only ever had one who was clever enough to realise that different brains see different patterns, and that one and the same mathematical problem can have more than one solution. Such teachers are few, but they make up for so much. :)

I'll have to make sure that when I have a child it gets the best education possible! Do they allow parents to join their child on classes at school? Like taking a look at what's the school like in action. I never saw it happening so I wonder if it's possible.

I'll have to make sure that when I have a child it gets the best education possible! Do they allow parents to join their child on classes at school? Like taking a look at what's the school like in action. I never saw it happening so I wonder if it's possible.

you could homeschool. ;)

you are right, I almost did it to her too, since 1+2=3 so the "add three" is incorrect, and since 2 is a prime number so it should have been 1, 2, 3, 5, 7

but I didn't, I let it slide, you know since she is 3.

Well, who said the pattern needed to include ALL prime numbers? Maybe it's only odd ones?
And the other pattern could well have been add two, add two, add three, add three, add four, add four.... :)

I was reading the other thread on IQ scores and I was thinking of a few things. I'd like to know the opinions of some people on this topic. I have my own opinions but I want to see what others say.

Can a person actively do things to increase his intelligence?

Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?

Is intelligence only one in a myriad of mind features that make a 'smart' person 'smart'?

I think intelligence can be increased, but the younger you are, the easier it is to tinker. So yes, I'd say it's partly hereditary, partly environmental (like most things).

Well, who said the pattern needed to include ALL prime numbers? Maybe it's only odd ones?
And the other pattern could well have been add two, add two, add three, add three, add four, add four.... :)

true.

I figure the fact that she is trying to think about it is a good sign, I won't grade anything other than for effort until she is about 5.

you could homeschool. ;)

Depends on where she is... Germany for example has "Schulpflicht", all children from age 6 to age 15 have to attend a school, unless there is a good reason for them not to. And if they have to be homeschooled, their teacher (parent or otherwise) will need a relevant teaching degree.

I don't see how though, wouldn't 'eq' be the measure of skill in and intuition that is applicable to interpersional relations and an understanding of empathy?

We might be using words different ways. I had this discussion with my friend and 'intelligence' has more than one meaning to him because he has a different vocabulary than I do.

So this is how I define those things:

Knowledge: Amount of information collected about a singular topic or variety of topics.
Creativity: Capacity to create new ideas.
Intelligence: Capacity to reason and interrelate ideas to find patterns. (Including ingenuity which is using novel approaches to correlate data.)
Widsom: Using or relating knowledge in a way that is most appropriate/most efficient in each instance.
Craft/cleverness: The ability to apply novel approaches (not necessarily to create them) to a variety of topic and finding 'loopholes' in information and reasoning.


Same definitions, but slightly different angle :

I would call a person smart who is creative, intelligent, wise, crafty and clever in all fields of life, not only some. And human interaction would be such a field.

you could homeschool. ;)

I already thought about that but the problem would be that as much as I'm good at math and physics, I'm bad at literature and geography. Maybe if it was possible to homeschool only certain subjects. Which I think is not.

yes, that's very true, for example I gave a worksheet to my child once with the sequence

1 3 5 7

and the instruction to "finish the pattern"

she finished it a few different ways, once with odd numbers, once with prime numbers, and once with a pattern based on

"add three, add two, add two, add three, add two, add two"

all three may have been correct, it would only depend on what I intended the pattern to be.

http://img108.imageshack.us/img108/3659/blondgeometryanswerjx0.jpg

intelligent? :D

http://img108.imageshack.us/img108/3659/blondgeometryanswerjx0.jpg

intelligent? :D

By way of solving the problem with the least possible effort, yes.
By way of passing the test, no.

Depends on what the aim of the person was :D

Depends on where she is... Germany for example has "Schulpflicht", all children from age 6 to age 15 have to attend a school, unless there is a good reason for them not to. And if they have to be homeschooled, their teacher (parent or otherwise) will need a relevant teaching degree.

Oh... Now that I think about it, I think we have something like that here as well :( I'll have to take a look at those things before my child reaches school age. (And that's really a lot of time because I don't have a child yet... and I don't even have a partner to have the child with :p But that's another story :) )

Oh... Now that I think about it, I think we have something like that here as well :( I'll have to take a look at those things before my child reaches school age. (And that's really a lot of time because I don't have a child yet... and I don't even have a partner to have the child with :p But that's another story :) )

You can never be too prepared :D

Depends on where she is... Germany for example has "Schulpflicht", all children from age 6 to age 15 have to attend a school, unless there is a good reason for them not to. And if they have to be homeschooled, their teacher (parent or otherwise) will need a relevant teaching degree.
true.
I already thought about that but the problem would be that as much as I'm good at math and physics, I'm bad at literature and geography. Maybe if it was possible to homeschool only certain subjects. Which I think is not.
homeschool co-op. ;)
Oh... Now that I think about it, I think we have something like that here as well :( I'll have to take a look at those things before my child reaches school age. (And that's really a lot of time because I don't have a child yet... and I don't even have a partner to have the child with :p But that's another story :) )
yeah, but remember the first 2 years are very important, you can do a lot with them then to help them forever.

I beg to differ. No amount of intelligence will ever let you gauge another persons emotions.
A lot of it is instinctive, but then again, so is intelligence. Keep in mind, intelligence is the ability to solve a new problem by thinking it over, not just applying knowledge (applying knowledge out of context would be a sign of intelligence)Why not? There is nothing magical about the processes your EQ-related abilities make use of that result in you ending up with the estimation you do. (and it is indeed nothing more than a half-arsed estimation, relying on specific, though rather complex, patterns in the observed person's behavior. which is why you are guaranteed to get it wrong if you observe someone different enough, a problem that many people with Asperger's have; people are just as bad at reading them accurately as they are at reading others. and what is worse, they are fully convinced that they are right, and refused to acknowledge the possibility that the person with AS might, in fact, feel different than they instinctually feel they do) It is in many cases very easy to gauge a person's emotional state in a purely intellectual way, though that is limited to cases covered by the models you have built. Were you to keep working on such models, providing you were capable enough, you'd eventually come up with something atleast as accurate as the instinctual "feeling" of someone's emotional state.

yeah, but remember the first 2 years are very important, you can do a lot with them then to help them forever.

You can always do a lot to help them forever, simply by not accepting crappy teachers. I did outsmart a number of them at school, but the problem I had was that my mother would invariably take the teachers' side.

We did, as a class, however, manage to make the school keep the good teachers and we actually managed to get rid of some of the crappy ones (I'm not sure if I ought to be proud of that, but back then I didn't care)... on the whole I'd say school taught me a lot more than what was on the curriculum :D

Why not? There is nothing magical about the processes your EQ-related abilities make use of that result in you ending up with the estimation you do. (and it is indeed nothing more than a half-arsed estimation, relying on specific, though rather complex, patterns in the observed person's behavior. which is why you are guaranteed to get it wrong if you observe someone different enough, a problem that many people with Asperger's have; people are just as bad at reading them accurately as they are at reading others. and what is worse, they are fully convinced that they are right, and refused to acknowledge the possibility that the person with AS might, in fact, feel different than they instinctually feel they do) It is in many cases very easy to gauge a person's emotional state in a purely intellectual way, though that is limited to cases covered by the models you have built. Were you to keep working on such models, providing you were capable enough, you'd eventually come up with something atleast as accurate as the instinctual "feeling" of someone's emotional state.

The difference is in the speed with which you can process that information.
In a normal conversation, a sudden change of expression can mean many different things. If you have to go through a process of consciously analysing the change, it will take up a lot of your concentration. Either you'll lose the plot, or there will be a pause while you figure out what happened. Either way, it will alienate the person you were conversing with.

An instictive reaction will be much faster, the conversation will go on uninterrupted, nothing socially awkward will happen.

Why not? There is nothing magical about the processes your EQ-related abilities make use of that result in you ending up with the estimation you do. (and it is indeed nothing more than a half-arsed estimation, relying on specific, though rather complex, patterns in the observed person's behavior. which is why you are guaranteed to get it wrong if you observe someone different enough, a problem that many people with Asperger's have; people are just as bad at reading them accurately as they are at reading others. and what is worse, they are fully convinced that they are right, and refused to acknowledge the possibility that the person with AS might, in fact, feel different than they instinctually feel they do) It is in many cases very easy to gauge a person's emotional state in a purely intellectual way, though that is limited to cases covered by the models you have built. Were you to keep working on such models, providing you were capable enough, you'd eventually come up with something atleast as accurate as the instinctual "feeling" of someone's emotional state.

That sounds much too complex :eek: I just stick to my natural behaviour and treat everyone the same every time :D And when they make a noticable (read: BIG) change in their expression, I just ask them "What is it?" :) It always worked and there weren't any problems with that approach though it's true I don't really talk much to people in real (I'm always scared when I have to) so I don't have much experience.

Why not? There is nothing magical about the processes your EQ-related abilities make use of that result in you ending up with the estimation you do. (and it is indeed nothing more than a half-arsed estimation, relying on specific, though rather complex, patterns in the observed person's behavior. which is why you are guaranteed to get it wrong if you observe someone different enough, a problem that many people with Asperger's have; people are just as bad at reading them accurately as they are at reading others. and what is worse, they are fully convinced that they are right, and refused to acknowledge the possibility that the person with AS might, in fact, feel different than they instinctually feel they do) It is in many cases very easy to gauge a person's emotional state in a purely intellectual way, though that is limited to cases covered by the models you have built. Were you to keep working on such models, providing you were capable enough, you'd eventually come up with something atleast as accurate as the instinctual "feeling" of someone's emotional state.
I know exactally what you mean. This is I think what many people do. I have always felt this way and I think it gives me greater insight into emotions that relying on some 'feeling' to see what is going on. It also allows a person to predict reactions more accurately based on information about the person.

Same definitions, but slightly different angle :

I would call a person smart who is creative, intelligent, wise, crafty and clever in all fields of life, not only some. And human interaction would be such a field.

I thought 'eq' was meant to mean a natural proclivity towards interacting with others and understanding their emotions. As Divine Imaginary Fluff mentioned above and I discussed, people who aren't naturally good at it can become good at it in a completely different way.

The difference is in the speed with which you can process that information.
In a normal conversation, a sudden change of expression can mean many different things. If you have to go through a process of consciously analysing the change, it will take up a lot of your concentration. Either you'll lose the plot, or there will be a pause while you figure out what happened. Either way, it will alienate the person you were conversing with.

An instictive reaction will be much faster, the conversation will go on uninterrupted, nothing socially awkward will happen.Indeed, that I won't dispute. My argument was simply that it was possible.

The processing-induced delay could be shortened significantly though. With experience, you gradually memorize enough things that you seldom need to do any complex analysis, and can quickly come to your conclusion. Much could also be kept in short or atleast mid term memory (as the short term memory is much smaller, and likely occupied by things related to the conversation), which can be accessed near-instantly, resulting in insignificant delays in many cases, quite small most of the time, and only rarely significant ones.

yes, that's very true, for example I gave a worksheet to my child once with the sequence

1 3 5 7

and the instruction to "finish the pattern"

she finished it a few different ways, once with odd numbers, once with prime numbers, and once with a pattern based on

"add three, add two, add two, add three, add two, add two"

all three may have been correct, it would only depend on what I intended the pattern to be.

now i'm not picking on how you are educating your children, or indeed on the children themselves but by definition a prime number is a number which has exactly two integer divisors: 1 and itself. therefore 1 is not a prime number as it has only one integer divisor (itslef). so wtf are you on about??? and explain to me the "add three, add two, add two, add three, add two, add two" thing... as far as i can see they are only going by adding 2: 1, + 2 = 3, + 2 = 5, + 2 = 7, and so on... and since no iq test author, or anyone sensible for that matter, would think of a pattern which is not fully exemplified at least once in the given string you can safely conclude that the only answer for that question is indeed 9

Although others have answered pretty much accordingly, I'll give it a shot none the less :p

Can a person actively do things to increase his intelligence?

Yes! People can actually train their brain as if it were a muscle - by simply using it. The more you think, the more frequently certain brain-routes are used which form thinking patterns. Forgetting (without physical trauma, that is) works pretty much the same way, because you demote certain routes from highway to backroad. They're still there, but less frequently travelled.

Your brain remembers which routes you travel frequently and keeps those open for traffic. But that doesn't mean you cannot pave other routes. (Like in relearning how to move, for example, after a head-injury.)

Is intelligence determined by heredity, childhood brain development, or something unrelated to brain structure?

Heredity gives you the roadmap.

Childhood brain development installs the first highways. The more you let your kid travel on different paths, the broader its network will develop.
Since those circuits are formed the easiest during the first 2 years, but especially during the first 6 months, it is highly important to give the kids as much intake as possible. Those impressions - be they sound, smell, taste, pictures - help shape and promote the thinking patterns that will later on form the routes it travels on while thinking.

Again, not completely unrelated to brain structure is its use. Your brain is learning all the time, even when you're supposedly not doing anything. It learns not to do anything, then.

So by using your brain actively, you are changing your brain. Maybe not the structure per se, but you're definitely rewiring the circuitry.

Is intelligence only one in a myriad of mind features that make a 'smart' person "smart"?

I would believe so, for intelligence is only one of very many traits that make us function in a "smart" way.
At least I try not to be a "Fachidiot". (Which literally translated means "subject idiot", an idiot but in one subject.)

http://planetsmilies.net/not-tagged-smiley-14297.gif