Paraesthesia was developed as a safer alternative to traditional anaesthesia. Rather than numbing the pain or sedating the patient, paraesthesia simply uses a temporary neural interface to feed alternative sensory information directly to the brain in the form of a computer generated simulation. While the patient is having a heart bypass or a dental extraction, their mind is happy elsewhere in virtual reality.

Since it requires no drugs to work, it removes any potential for adverse physical reactions and the role of anaesthesiology can be replaced by that of a minimum-wage technician.

With early designs, there was a tendency for real-world pain signals to begin to intrude upon the simulation. This was overcome by partially overclocking part of the brain, thereby dilated the apparent time within the simulation. At x10 dilation, the sensation of even a highly invasive procedure is spread out, becoming only a sharp ache within the simulation; at x100, a mere itch.

As with any medical technology, there were risks of complications, usually as a result of ill-trained or negligent technicians inputting incorrect parameters. Patients would occasionally be made to sit through simulations intended for others or have to endure hours or days of something that was intended to last minutes.