Old dogs and new tricks

I've always held that the average human being's command of the English language starts dropping sometime between graduating high school and graduating college, and keeps dropping after that unless conscious measures are taken. We find it progressively difficult to maintain our fluency, leave alone improve. We become better at saying the things we are used to saying, but worse at the rest. I hunt and grope for words I know I know, but can't remember exactly, and settle for imperfect substitutes or long-winded explanations. For example, I wanted to say "esoteric" last week, but my memory failed me and I stuttered and ended up asking, "What's the word for known to a select few?"

I'm yet to reach a verdict on whether things work the same way with my courses and research. If I don't apply my knowledge of some field for a while, no matter how basic it is, will I forget? Am I finding it hard to learn some new topic simply because it is a difficult subject, or is it because I'm losing the will or capacity to learn new things?

Is it harder to teach an old dog new tricks because the old dog doesn't want to learn, or because the old dog finds it more difficult to learn? Are they, in fact, one and the same thing?

Alright, I know I'm just 23 and hardly an "old dog", but I swear my patience for course work is nowhere near what it used to be. Did I lose the inclination, or the capacity, or do I still have both but just feel insecure?

These are sad times indeed, when I need to fortify myself with caffeine to get work done. Time was, when I would perk up on looking at the problem and get through it with adrenaline instead of caffeine.

Cheers,
Prashanth.

Last book I read: Equal Rites by Terry Pratchett