|MadSci Network: General Biology|
Well, that is an interesting and complicated question you ask, and there is no simple answer. For one thing, what does "intellectual peak" or "intellectual prime" really mean? Intellectual ability or performance is made up of many different things (like verbal ability, mechanical ability, musical ability, and ability to remember things), and there are many different things that can affect people's performance. For example, I bet you score better on tests in school if you eat a good breakfast that morning and had a good night's sleep the night before, and I bet you wouldn't do so well if you had a headache or a cold or were really mad at your teacher or the kid sitting next to you in class. With so many things to take into account, it would be impossible to say that there is a typical age at which people reach their intellectual peak. If you want to talk specifically about short-term memory, then I guess the answer would be that probably by the time kids are in their teens, or maybe even earlier, they have reached the full capacity that people have to remember things they have just heard or read. Then short-term memory pretty much stays the same (for example, it is a general rule that people have the ability to remember five to nine items at a time). People can lose the ability to remember that much in short-term memory for a number of reasons, like illness, damamge to the brain, or medication side-effects. But that level of memory mostly stays the same, for both men and women, unless something goes wrong. I hope this answers your question. How thinking and and memory work are very interesting areas of study, and many psychologists and neuroscientists do research to understand these things better, but there's still a lot we don't know.
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