EEG-Responsive Sound Worlds
An authored acoustic world that keeps its sources, supports and process consequences — while its presentation adapts to the listener's attention, relaxation, fatigue and meditation.
Abstract
Soundscapes that follow the body must keep their world intact while the signal changes.
Physiologically responsive soundscapes must accommodate changing control signals while maintaining the identities and consequences of audible events. NeuroJourney is a macOS prototype that separates persistent world processes from their adaptive acoustic presentation.
A scene is authored through source identities, support regions, process dependencies and a sparse cue budget. An EEG interface supplies quality-gated vendor indices for branch selection, permitted motion and bounded audio control. Local and optional cloud planners submit recordings to a common executor that checks admissibility before and after asynchronous preparation.
Two artistic cases develop the approach: a cave whose inhabitants are disclosed through distributed cues, and a rainy shelter whose vessel progresses from heating to serving. Evaluation combines 34 contract checks, controlled component ablations, scene traces and archived digital renders.
Four Worlds
Every new journey begins on the ship. Stable, quality-gated EEG features gate entry into one of four branches — and a chosen branch never advances on its own.
distributed evidence
Embers sustain a resting place, faint opening air marks a boundary, a localized seep binds moisture to one rock surface. Sheep calls are distributed across four anchors; low breathing introduces the giant through an ongoing bodily process — present even in the intervals between breaths.
the goddess's shore
Water, distance and presence are composed as a single continuous suggestion. The branch affinities favour the oriented meditation coordinate, letting attention settle rather than pursue.
a threshold of hospitality
A threshold of hospitality where ambience and enclosure are tuned by authored acoustic profiles. Relaxation dominates the branch mapping here; the courtyard rewards staying rather than arriving.
an unfolding process
Exterior weather persists while an interior vessel heats from 52 °C, crosses its first-boiling threshold at 99.7 °C and becomes eligible to serve fourteen seconds later. Lowering the vessel's salience never cools its water — presentation does not determine process truth.
Mechanism
The contribution is an execution architecture: world processes, object permissions and acoustic presentation share one admission path.
During active, unpaused simulation the world advances independently of the signal. A pause freezes process time; restoration preserves recorded process facts, so a completed heating can never be silently replayed.
Asynchronous decoding opens an interval in which conditions can change. The sound contract is validated again at the voice boundary, and the executor rechecks playback state, scene, deadline, prerequisites, capacity and spacing immediately before source start.
Four vendor indices — attention, relaxation, fatigue, meditation — pass eligibility, calibration, median and deadband filters before smoothing with a 2.5 s time constant. Invalid or stale input returns control toward a fixed reference, preserving active processes.
Publication
NeuroJourney is the prototype behind this paper, submitted to CCAC 2026. It reports execution properties of the implemented system and exposes the remaining perceptual and physiological questions.
The evaluation deliberately separates what the software enforces from what a listener perceives: listener understanding and the value of live EEG remain empirical questions.