Sky to broadcast adverts directly into train passengers' heads The proposal involves using bone conduction technology, which is used in hearing aids, headphones and Google's Glass headset, to pass sound to the inner ear via vibrations through the skull. Some people don't like advertising in general. But this is really a new technology. [It might] not only be used for advertising, but also for music, entertainment, mass transport information, weather reports and so on. Sky Deutschland said it had not made a decision on whether to launch the campaign.