5 out of 5 stars
I noticed the difference esp after 30 days. The proof that it wasn't all in my head was this. 5 years ago I took a memory & mind test. Well, my scores on this test actually IMPROVED from 5 years ago. I have some problems with the test itself. I would have done even better. So I'm truly excited & am getting my wife on them now too. I'm 72 & wife is 77.
4.7 out of 5 stars (320 ratings)