As always when taking medications, even ones that don't seem like they might affect brain functioning, it's important to pay attention to potential side effects. Statins are medications like Crestor and Lipitor the help control cholesterol levels. These medications can affect myelin sheaths that help our brains conduct electrical signals, resulting in potential impact on learning and memory. Scientific American weighs in:

Two small trials published in 2000 and 2004 by Matthew Muldoon, a clinical pharmacologist at the University of Pittsburgh, seem to suggest a link between statins and cognitive problems. The first, which enrolled 209 high-cholesterol subjects, reported that participants taking placebo pills improved more on repeated tests of attention and reaction time taken over the course of six months—presumably getting better because of practice, as people typically do. Subjects who were on statins, however, did not show the normal improvement...

That said, it's important to recognize the typical nature of research:

But other studies have found no significant link between statins and memory problems. Larry Sparks, director of the Laboratory for Neurodegenerative Research at the Sun Health Research Institute in Sun City, Ariz., goes so far as to say that “you’ve got a better chance of buying a winning lottery ticket, walking outside and getting hit by lightning and dying” than you do of suffering a cognitive side effect from statins.

Just remember to pay attention to what's happening with you and if you notice a change in your cognitive functioning, bring it up. Better to be aware than to ignore something so simple yet important. This also reinforces the notion that there are pros and cons to taking medications and in some instances it may be better to control your cholesterol behaviorally rather than medically.