The main character of John Scalzi’s Lock In, Chris Shane, is a police detective who has a disability known as Locked-In Syndrome. Chris developed the disability after falling to a disease known as Haden’s syndrome as a child. The disease known as Haden’s syndrome may be fictional, but Locked-In Syndrome is an actual condition.
Most real-life cases of Locked-In develop as a result of a stroke or damage to the brain stem. People who have Locked-In Syndrome are fully conscious and aware of their surroundings, but they are physically incapable of interacting with those surroundings or communicating with others by normal means. The only movement usually available to someone with Locked-In Syndrome is eye movement.
That does not mean that people with this medical condition are incapable of living rich and full lives. The virtual reality world and the ability to control a robot body may not yet exist as it does in John Scalzi’s novel, but existing technology allows people to control an astoundingly large number of tools with just eye movement. There are wheelchairs, voice synthesizers, word processors and more that all respond to eye movement. Stephen Hawking arguably has Locked-In Syndrome as a result of ALS, but his rather famous voice is controlled by a voice synthesizer that he controls with his eyes.
To learn more or hear some real life tales about living with Locked-In Syndrome, please check-out the following links.