Subvocalization is a form of silent speech that occurs when a person is reading silently yet still hearing the words in her head as she reads. Though it can appear in the form of the person moving her lips without making any noise while reading a book, more often the person does not appear to be moving her lips at all. Despite the appearance, small movements are actually occurring, yet because they are so minuscule, it takes the advanced technology of a machine with sensors attached to the person to pick up on these tiny movements.
As the brain reads a sentence, it prepares to say each word aloud. Even if the reader never actually says the word, the tongue and vocal cords still make small movements in preparation for reciting the word. This occurs because people learn words first by sound and then by sight. Thus, seeing a word on a piece of paper automatically brings to mind the way it sounds and how to pronounce it. Scientists believe that subvocalization increases memory and that without it, it would be much harder to interpret and remember what is being read.
The field of speed reading claims to increase a person's reading speed by eliminating the process of subvocalization. Much debate exists over whether or not it can, in fact, be eliminated. Though speed readers, who often skim pages instead of reading word for word, do show lower levels of subvocalization, it still seems to be present. Studies suggest that attempting to eliminate subvocalization, if possible, might actually lower the amount of material the person remembers.
Modern technology can detect the small movements made during subvocalization by monitoring electrical impulses. As of 2011, the National Aeronautics and Space Administration (NASA) is working on technology to detect these forms of silent speech. By reading these faint electrical impulses that occur during the process of subvocalization, machines could appear to read a person's mind and respond seemingly without the person saying anything. All the person would need to do is clearly think the command he wants the machine to carry out.
Research into the detection and use of silent speech for controlling technology opens the door for several new scientific fields of study. It could help those with speech problems communicate through the use of a machine. It has many medical uses and also uses for entertainment purposes. A video game could be controlled using this form of subvocalization recognition, allowing the player to appear to control the game with his mind. Though the concept is not advanced, its applications may lead the way to an entirely new form of interacting with technology.