Does Search-a-word Puzzles Really Improve Memory?

With all the talk today about dementia and keeping your memory by doing puzzles, specifically crossword, I wonder if doing search-a-word puzzles also have an impact on retaining memory or just crossword.

Suggestion:

It's not so much about retaining or improving one's memory as it is about keeping the mind active.

As it is said applied to physical and mental health, if you don't use it, you'll lose it. If you don't use your mind, it will atrophy and become a void. Any activity that gets the 'mind moving' and thinking is good.