Sudoku vs Crossword Puzzles: Which Is Better for Your Brain?
Different. I do both. Crosswords for words, Sudoku when I want to switch off language.

Crosswords are about words, vocabulary, trivia and puns. You have to know things. I like crosswords when I need to find a seven-letter word for ancient vessel. "They are working a different part of the brain, the language part," explains Dr. King.
Sudoku does not matter whether you know the language or not. It is about numbers and logics. The same Sudoku grid can be solved by anyone from Tokyo to London. It is more relaxing than other puzzles, he said, because there is no need to know anything. Many people find Sudoku boring, he disagreed.
But Can You Really Die From Too Many Crosswords? (Well, not really, but that's the title of an article I just read in the Times) Apparently, puzzles like number and word puzzles "work on different parts of the brain. Crosswords for example, make use of the temporal and frontal lobes of the brain which are centred around the functions of language. Sudoku "works the brain's spatial reasoning as well as cognitive functions such as executive function." Great, thanks for the info, but I'm not really here to want to discuss or learn more about the inner workings of the brain through Sudoku. Go ahead and read the article if you're interested, though.
I would say that they are about equal in value to each other. I do crosswords when I am in a humorous or clever mood and I do Sudoku when I am in the mood for a change of pace from words. Perhaps the sum of both activities is more rewarding than either one alone. Perhaps the law of gym exercises applies here as well. Each type of exercise is important in of itself.
If you only have time for one which will you choose to do? Challenge your vocabulary with crosswords Develop your problem-solving skills with Sudoku WHICHEVER YOU CHOOSE puzzles will engage your mind and entertain your senses. Choose a puzzle that works for you.