Lacunal Drift is a genre composed exclusively for direct neural-feed delivery — it has no audio component whatsoever, and played through conventional speakers produces only silence or faint subaudible hiss. The genre emerged in the 2190s from BCI researchers and underground artists who realized the neural feed could deliver not just simulated sound but texture, spatial memory, and emotional color simultaneously. A Lacunal Drift composition typically layers three to seven 'streams': a tonal field that the brain interprets as something between sound and temperature, a spatial scaffold that creates the impression of enormous or intimate architecture around the listener, and an emotional undertow — not a forced feeling, but a resonant suggestion, the way a key change in an old song implies loss without stating it. The genre's name refers to the lacunae — the gaps — that define the experience: what is not transmitted is as important as what is. Listeners describe it as 'hearing a room you've never been in' or 'the feeling of a word you almost remembered.'

The genre originated in Tier 3 and 4 research circles but spread rapidly downward through pirate feed networks, where stripped-down versions circulated on the Shelf among those with even basic BCI implants. Purists argue that cheaply-implanted Tier 1 BCIs lack the bandwidth to receive full Lacunal compositions, and that what Shelf listeners experience is a degraded smear of the original — but Shelf practitioners counter that the degraded form is its own valid tradition, rawer and more honest. Vantablack Media has attempted to commodify the genre twice, producing polished Lacunal releases that critics called 'architecturally correct but emotionally inert.' The underground scene has never forgiven them.