Scalextric-style slot cars that can be controlled with your brain -- going faster the harder you concentrate -- were demonstrated at the Consumer Electronics Show. Attendees at the technology event -- held in Las Vegas in the US -- wore headbands based on medical brain-scanning tech to race model cars about a track. The company behind the mind-reading technology is Massachussets-based firm BrainCo, which grew out of Harvard University's Innovation Lab. The slot car setup worked by using the Focus1 headbands to non-invasively measure participant's brain activity and transfer this to a paired model car on the racetrack. The technology is based on conventional electroencephalograms.