What are the physical differences between the brains of people with average/slightly above average IQs and people with very high IQs?
What are the physical differences between the brains of people with average/slightly above average IQs and people with very high IQs?
Intelligence is not a measure of how powerful your brain is as a whole, but how well it does a certain type of task. IQ is mostly a logic test. Lots of things can contribute to how your brain performs logical functions. Math and logic are mostly attributed to the left side of the brain while artistic abilities are attributed to the right side of the brain. Having less development in the left side of the brain for whatever reason (smoking while pregnant) can cause IQ to drop. Physical damage to the left side of the brain because you were dropped as a baby will make your IQ drop as well.Many other things associated with intelligence are not directly related to the shape of the brain.
Medications given to children with attention problems are often amphetamines which work by increasing dopamine and noradrenaline in the brain, and this can have a very large effect on measurable intelligence. Dopamine has profound influence on how well a person can remember things, concentrate, and put their thoughts in a logical order. A brain with low levels of dopamine will often be confused, and it will be thinking of lots of conflicting ideas without being able to choose one. Have you ever felt overwhelmed with lots of things to do, but you're completely unable to start doing anything because you don't know where to start? Low dopamine brains operate like that. A brain surging with dopamine will pick a logical starting point and try to build a plan: first I solve for X, then I integrate it by Y, then I divide this by Z; dopamine makes math and logic a lot easier.
Understanding the effect drugs have on intelligence paints a picture of how specific parts of the body influence intelligence. For example, a brain with very high sensitivity to dopamine will probably be smarter than a brain with low sensitivity. The person with high sensitivity will be a bit of a dreamer who can space out a lot and be totally lost in their own thoughts, and the ability to space out and completely disconnect from outside stimulation is useful when trying to solve a problem. People who lack the ability to be lost in thought will find themselves distracted a lot; everything breaks their concentration. It's hard to get the right answer with all these distractions.
Outside of obvious defects, I don't think you can look at an X ray or anything and get an accurate estimate of intelligence. There might be some correlations with number or degree of sulci (the little grooves on the outside), but I don't think that's really known.
Yes,I understand all that.Also,just to clarify,when I mean physical differences,I don't just mean a difference in the shape of the brain but also differences in neurotransmitter levels and the sort.Correct me if I'm wrong,but technically speaking,doesn't everything that we think or feel,have a physical basis in the brain?I mean,the mind is more of an abstract concept versus the physical brain isn't it?
What happens when dopamine,noradrenaline and other neurotransmitter levels are altered(particularly increased even more) in normal people(i.e. people without deficits in attention and a healthy IQ)?
Does it in any way make them smarter/more logical?(Although I guess logic is something that arises due to a symbiosis of many factors and not just neurotransmitter levels.)
I have so many ideas and questions which I can't really put together(some of them might sound downright silly).I'm probably one of those low dopamine brains you're talking about. :|
Probably due to the limitations of today's imaging techniques/instruments?
Which brings me to my next question,what are the things that today's imaging techniques CANNOT tell us about the brain?
NOTE: Please forgive me if I sound downright silly anywhere.Neurology is something that is intriguing and I'm just asking questions to learn more.I'm not a guru at this.
IQ will still increase up until a certain point. This is why a lot of engineering students who are already very intelligent start taking Dexedrine or Adderall at university. It makes you more intelligent, more focused, able to work longer, study longer, retain information better. At a certain point it stops making one smarter and starts making them crazier. When you get to that point, it's called "stimulant psychosis" and it lasts for as long as you are under the influence of that drug. It's often said that there is a fine line between genius and insanity, and that's actually true. The same parts of the brain responsible for spacial thinking and the ability to dream are also responsible for hallucinations and the ability to dream this stuff while you are still awake. People who have these uncontrolled dreams/nightmares while they are awake are called schizophrenics, and their medication works by lowering dopamine activity. It's so fascinating how that's all tied together! It also doesn't come as a shock when those dopamine-lowering schizophrenia drugs tend to make people very tired, confused, and have horrible attention spans.What happens when dopamine,noradrenaline and other neurotransmitter levels are altered(particularly increased even more) in normal people(i.e. people without deficits in attention and a healthy IQ)?
You're right about many different factors contributing to it. For example, the medication I take for my chronic low blood sugar is a very powerful dopamine/noradrenaline stimulant. While those neurotransmitters in the brain definitely do things, the main reason this medication makes me feel better and think faster is because it raises my blood sugar and increases blood circulation. My brain could have all the dopamine in the world and it wouldn't make a lick of difference if the brain had no fuel to burn (ie blood sugar). Whatever is the biggest bottleneck will obviously make the biggest difference. If you're incredibly tired, a good night sleep will make you smarter than any pills will. After you've had a great night sleep and no longer need sleep, the pills have a stronger effect.Does it in any way make them smarter/more logical?(Although I guess logic is something that arises due to a symbiosis of many factors and not just neurotransmitter levels.)
IQ will still increase up until a certain point. This is why a lot of engineering students who are already very intelligent start taking Dexedrine or Adderall at university. It makes you more intelligent, more focused, able to work longer, study longer, retain information better. At a certain point it stops making one smarter and starts making them crazier. When you get to that point, it's called "stimulant psychosis" and it lasts for as long as you are under the influence of that drug. It's often said that there is a fine line between genius and insanity, and that's actually true. The same parts of the brain responsible for spacial thinking and the ability to dream are also responsible for hallucinations and the ability to dream this stuff while you are still awake. People who have these uncontrolled dreams/nightmares while they are awake are called schizophrenics, and their medication works by lowering dopamine activity. It's so fascinating how that's all tied together! It also doesn't come as a shock when those dopamine-lowering schizophrenia drugs tend to make people very tired, confused, and have horrible attention spans.
So there's your spectrum. On one side you have sanity and low intelligence. On the other side you have super genius with super schizophrenia and/or manic episodes. Normal people, if they want, can take a bunch of amphetamine to become super smart then have a crazy manic episode where they buy a $3000 computer because it was a good idea at the time
You're right about many different factors contributing to it. For example, the medication I take for my chronic low blood sugar is a very powerful dopamine/noradrenaline stimulant. While those neurotransmitters in the brain definitely do things, the main reason this medication makes me feel better and think faster is because it raises my blood sugar and increases blood circulation. My brain could have all the dopamine in the world and it wouldn't make a lick of difference if the brain had no fuel to burn (ie blood sugar). Whatever is the biggest bottleneck will obviously make the biggest difference. If you're incredibly tired, a good night sleep will make you smarter than any pills will. After you've had a great night sleep and no longer need sleep, the pills have a stronger effect.
Probably due to the limitations of today's imaging techniques/instruments?
Certainly, but I think it's worse than that - we don't fully understand all the information that we can get right now.Which brings me to my next question,what are the things that today's imaging techniques CANNOT tell us about the brain?
It all depends on how your IQ is measured, you might score low on an IQ test but have great potential intelligence. You are ignorant if you have not learned something, that does not make you "stupid". My favorite expression is "IQ is a measure of your knowledge base, not your actual intelligence (your capacity for learning)".