
Carl K. answered 09/15/19
Assistant Professor of Family Medicine
The purpose of stimulants like Ritalin, or simple caffeine, for example is to prolong study time by reducing the need for sleep. There are a number of studies which confirm that lack of sleep reduces learning, retention, and test score performance.
When Ritalin is used properly by students who have ADHD, is has a paradoxical effect compared with other students, in that it allows them to focus, to concentrate on their lessons, and to learn better.
Most authorities will agree that one of the best ways to do well on an exam is to get a good night's rest beforehand. When you are well rested, your brain is performing optimally, you are fully charged with neurotransmitters, etc. and you will perform at your best.
Long term learning and retention is best accomplished by repetition, studying over a longer period of time, taking frequent breaks, etc. In other words, "cramming" or short-term, last-minute, prolonged study is counter-productive.