This patient underwent an fMRI to localize language preoperatively.
Patients are asked to perform specific tasks while being imaged, such as motor activity (see image) or verbal tasks. The relevant parts of the brain will therefore demonstrate increased signal.
Incidentally, I read a cool article earlier today entitled: Numbers Guy: Are Our Brains Wired for Math? It's primarily about a researcher who uses brain scans to study how the brain processes numbers. Here's a quick excerpt:
Because Chinese number words are so brief—they take less than a quarter of a second to say, on average, compared with a third of a second for English—the average Chinese speaker has a memory span of nine digits, versus seven digits for English speakers. (Speakers of the marvellously efficient Cantonese dialect, common in Hong Kong, can juggle ten digits in active memory.)
Also on the subject, I suppose. Another blog of mine: counting people.
