I'm also wondering how to distinguish between somebody who does not use their academic ability (could do awesome but they're lazy, don't try, discouraged, whatever) and someone who couldn't succeed no matter how hard they tried because the academic ability is not there. This determination is NOT easy to make.
I don't know that anyone can really distinguish between someone not using their academic ability and someone who couldn't in the typical normally functioning person, except perhaps the individual themselves; they are the only one that knows if they are giving something their all. Even then, there are things that might be impacting that person that even the individual isn't aware of (like dyslexia.)
Also you hear sometimes about games and whatnot that will "make you smarter". A person can become smarter? What does this say about academic ability? Is it not static? Is it something that will grow with use and with the accusition of study skill knowledge?
the more connections you make in your mind, the easier it is to pick up new information and integrate it into the information you have. IE if you understand the physiology of the kidney, it's easier to understand pharmacological impacts, pathology, etc. If you understand arithmatic, algebra and geometry are easier, and if you understand those, calculus is easier. Now, there are still some folks that are going to be better or worse at those. IE - my autistic cousin can ID every song he ever hears by name and artist after hearing it only once. I can't ID any artisits by songs, and can't remember any lyrics. I can do calculus, he can't get past division. Now, could we both make progress if we worked really hard on our weak areas? probably, but is it the best use of our time and how would it make us feel?
I am struggling with wanting to know the answers to these questions: can someone, assuming they don't have a mental dissability, really be "stupid" or is it a myth perpetuated by people who get frustrated easily? (Note: No offence intended toward people who have true mental dissabilities.)
Hmmm...I don't tend to use that word, so that's hard to answer. I had a friend in high school that a lot of folks would have called stupid. He studied intensely (far more than I did), worked really hard, was a very nice, kind guy. I feel confident he gave his all, all of the time. No matter what, he was always a C/D student. I have so much respect for him, because I think it was far harder on him than it was for me. I imagine he felt, in high school, like I do in vet school (where some courses, no matter how much I study, can I get above a C in.)
I do feel stupid when I make foolish mistakes. When I panic during an exam, or look back on an exam and wonder 'why on earth did I mark THAT answer?' I also always wonder 'would it have been better if I studied more? and sometimes the answer is yes, but sometimes the answer is no (I;m really terrible at memorizing random details.)