In a new study, researchers used a type of brain scan called fMRI to record brain activity in three people as they watched hours of Hollywood movie trailers. Brain signals were fed into a computer program that learned how each person’s visual system responded to scenes in the movies. Once the computer program had a good handle on the brains’ responses, the researchers went backwards and attempted to re-create what people were watching solely on the basis of brain signals. The basic physics of an fMRI isn’t difficult. A patient is first of all placed inside a large magnet and radio waves are then used to excite the nuclei of hydrogen atoms within the patient's body using an external coil. After this step of applying radio-frequency excitation, the hydrogen atoms emit energy at the same radio frequency until they gradually return to their equilibrium state. These radio waves are detected using an external coil, measures the sum total of the emitted radio-frequency energy, digitized, processed by a computer and displayed as tomographic slices revealing the distribution of different tissues.

Right now, the technology only allows for the detection of stationary objects and doesn’t read emotions. However, if we combine the ever increasing potential of brain scan technology and the ease in which computers can scan through large amounts of data in no time at all, there could come a time where any scanner will be able to read exactly what you are seeing, thinking and feeling. Welcome to the future of technology.

http://www.sciencenews.org/view/generic/id/334808/title/The_minds_eye_revealed_