Virtual Reality was getting to be a big topic by the early 90s. However, a lot of the treatments that we read depicted it as little more than an extended form of computer game, usually with plot lines aimed at a fairly juvenile readership. And then there were those that used it as an advanced form of simulator for teaching certain skills or familiarizing space explorers, military personnel, intelligence agents, or whomever with various problem-posing environments--often leading up to a ghastly ending in which the secret was revealed that it had really been VR all along.
I decided to look for a more challenging application for such an intriguing technology. Also, I wanted to get away from the ubiquitous helmets, gloves, and body suits the had become standard supporting props for this kind of story. (Like the starships with control sticks and paper-tape-fed computers of an earlier generation of stories, it was funny how technology seems to freeze at the level of whatever is current at the time of writing.)
So I hypothesized a direct neurally coupled technique, bypassing the sensory channels and interfacing straight into the brain centers to produce a total sensory illusion. This in itself wasn't original--I'd used an alien version of it myself in GIANTS' STAR, back in 1981--but to add some background flavor I wove in a fictional account of how it had developed out of various things going on at the time (i.e. the early 90s) that many readers would be familiar with, and of which the events in the book were partly the outcome.