If you open an acct with The Great Courses you will have access to some free material, one of them being an excerpt from this course (which I have linked below).
The Great Courses also comes in other formats. I have plenty of courses on MP3 and they are great during magic sessions when acquiring proficiency in a rote sleight or routine may become tedious to the brain. I find having the brain have something else to munch on pleases its need for further stimulation other than the magical minutiae we magicians often enslave it to. Of course, classical music works just as well, but I think the brain likes to show off its stuff as The Secrets of Mental Math will happily teach you.