Does caffine help cognitive ability when one hasn't gotten enough sleep?

Coffee is a stimulant, if that's what you mean. People think more when they drink coffee, but we can't be sure if they think any better.

When you sit, roll your hips forward so your back is straightened and does not touch the chair. You will notice an immediate improvement in breathing and alertness, and you can stay awake through almost anything as long as you don't slip back into a slouch.