There are lots of tests out there that all correlate with general mental ability. Some of these, like mental rotation tests, benefit a lot from practice. Some

There are lots of tests out there that all correlate with general mental ability. Some of these, like mental rotation tests, benefit a lot from practice. Some of them, like Raven's Progressive Matrices, don't. The tests used in modern IQ tests are the ones where practice don't give much benefit.