Mayim Bialik
This image appears in the gallery:
7 Celebrity Brainboxes. Who knew!

2. Mayim Bialik
The Big Bang Theory star not only portrays a science genius on TV, she is ACTUALLY one in real life. After starting out her career as a child actor in 90s sitcom 'Blossom', Mayim took time off from acting to attend UCLA, where she completed a triple major (Hebrew, Jewish Studies and neuroscience) for her undergrad degree. After that, Bialik decided to go for the gold, earning a Ph.D in neuroscience from the school in 2008. Wowza!