Guess what I'm thinking about

On this month’s Scientific American magazine there was an advertisement for a machine that can read the cerebral activity. The device from a Japanese company called Hamamatsu looks like those helmets with pipes and lights worn by any stereotyped scientist on TV or movies. The text explains that there are already similar readers of cerebral activity in the market. However theirs uses light, instead of radiation or magnetic fields, being safer (if they say so, we have to believe). The ad still goes into technical details but the most interesting part is the utility of such mechanism: to find out if a head is actively working on a task or in a state of rest. Maybe that will be the true Big Brother, not a camera filming citizens all the time, but something that will have to be worn in the work place to check if you are really elaborating on a spreadsheet, or simply looking at the screen with the weekend in mind.