Many people take caffeine always, or never. But the evidence is clear: for some tasks, drink coffee -- for others, don't.
- Impairs hippocampal neurogenesis and long term memory
- Narrows focus -- aiding short-term memory when the information is related to the current focus of thought, and making short-term recall more difficult when the information isn't related
- Increases short term recall of both true and false memories
- Increases short term memory and attentional control
- Increases memory retention and retrieval
Use caffeine for short-term performance on a focused task (such as an exam).
Avoid caffeine for tasks that require broad creativity and long-term learning.
(Disclaimer: The greater altertness, larger short-term memory capacity, and eased recall might make the memories you do make of higher quality.)
At least, this is my take. But the issue is convoluted enough that I'm unsure. What do you think?