A closed-loop auditory environment designed to facilitate effortless transcending. No guided voice narration. Pure physical sound entrainment.

The Automatic Self-Transcending (AST) Meditation Lab (/meditation) represents the peak of our neuroacoustic research. While traditional meditation apps rely on guided spoken instructions or relaxing soundscapes, the AST Lab is designed for complete cognitive silence ("Brain-Quietness"). It uses a browser-native WebAssembly DSP engine to synthesize phase-locked harmonic frequencies and sub-Hz respirational pacing signals directly on the client.

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[!WARNING] REGULATORY STATUS & MEDICAL DISCLAIMER The AST Meditation Lab is strictly a stress-reduction, cognitive conditioning, and focus entrainment environment.

• No Medical Claims: The Brainstorm Reactor deliberately makes no clinical, diagnostic, or therapeutic claims regarding this software.
• Not a Medical Device: This application is not certified under the European Medical Device Regulation (MDR 2017/745) and is not intended to diagnose, treat, prevent, or cure any psychological or physiological condition.
• Contraindications: Individuals diagnosed with severe psychiatric conditions (including schizophrenia, bipolar disorder, borderline personality disorder, or clinical depression) must not use this software without active supervision by qualified clinical professionals.

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The Onboarding Safety Gate

Upon accessing /meditation, users are presented with a non-bypassable Medical Pre-Screening Safety Gate. Access is blocked until the user manually reviews and explicitly accepts the four exclusion criteria:

1. Absence of clinical psychiatric diagnoses (e.g., schizophrenia, bipolar disorder, borderline, severe trauma).
2. Absence of active hallucinatory or dissociative states.
3. Explicit acknowledgment of the non-medical nature of the software.
4. Agreeing to use the application solely for stress reduction, cognitive training, and personal focus development.

This gate ensures absolute compliance with European consumer safety regulations (UWG/HWG) and minimizes liability risks by establishing a clear boundary between wellness software and clinical devices.

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1. Synchronized Visual Respiration Pacer

During the initial phase of meditation, visual breathing pacing helps stabilize heart rate variability (HRV) and respiratory sinus arrhythmia (RSA).

• Phase-Locked Synchronization: The visual "Inhale / Exhale" pacer text and the scaling of the central circle are directly coupled to the DSP engine's 0.2 Hz sub-Hz LFO accumulator inside the AudioWorklet thread.
• Dynamic Adjustability: If the breathing frequency parameter is modified, the visual pacing animation and the physical sub-Hz envelope modulator in the sound stream adapt instantly and remain 100% synchronized.
• Rhythmic Stability: No duplicate opacity flickers or jittering; the pacer text remains rock-steady, preventing involuntary visual attention tracking.

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2. Adaptive Visual Auto-Dimming (Calm UX)

Visual pacing is critical at the start of a session but becomes a source of sensory stimulation once the user closes their eyes. To support sensory deprivation, the AST Meditation Lab implements Adaptive Auto-Dimming:

Note: Crucial session controls (Initialize, Suspend, Reset) remain at 100% opacity at all times to ensure blind accessibility.

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3. The Expert Calibration Accordion

To preserve cognitive serenity and prevent restless manual adjustments ("fiddling") during the session, all four diagnostic parameter controls are housed inside a collapsible Expert Calibration Accordion:

• IAF (Individual Alpha Frequency): Tunes the central alpha modulation carrier (range: $8.0 - 12.0\text{ Hz}$) to match the user's personal occipital alpha baseline.
• Brown Noise Volume: Sets the stochastic resonance level (uncorrelated brownian noise) to block external acoustic perturbations.
• Master Volume: Calibrates auditory output (physically restricted to a minimum floor of $0.05$ / $20\text{ dB}$ SPL to avoid homeostatic dorsal cochlear nucleus hyperactivity).
• Respiratory Rate: Adjusts the sub-Hz visual and auditory pacing frequency (range: $0.05 - 0.25\text{ Hz}$).

The accordion is hidden by default. The user performs a one-time calibration, collapses the panel, and enters the session without visual distraction.

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4. The Science Panel

Accessible via the "The Science" button in the header (represented by a clean DNA icon), the right sidebar sheet provides absolute transparency regarding our neuroacoustic parameters. The copy is written in English standard academic voice and discloses the six functional pillars:

1. Just-Intonation Carrier: Phase-locked pure harmonic carrier frequencies (400, 500, 600, 800 Hz) in strict 5-Limit Just Intonation. Avoids prefrontal event-related potential (ERP) error waves caused by 12-TET tuning.
2. SVF Respiration Pacing: Sub-Hz State-Variable Filter (SVF) modulation at 0.2 Hz to stimulate respiratory sinus arrhythmia.
3. Speech Envelope Suppressor: Dual SVF-based suppression of the 4–8 Hz speech envelope. Starves the brain's language processing centers, suppressing narrative self-referential loops without uncalibrated hemodynamic assumptions.
4. Real-time LZ76 Complexity Monitor: Downsampled envelope complexity tracking on a 2048-sample sliding window to evaluate the depth of self-transcendence in real time.
5. Rössler Chaos Injection: Injects sub-threshold, unhearable 4th-order Runge-Kutta (RK4) Rössler chaos when complexity drops below 0.22, preventing habituation.
6. Vigilance Stabilization (R_ATC): Real-time monitoring of drowsiness. Applies a 20° interaural phase difference (IPD) spread and a -40 dBFS Beta-1 (16 Hz) rescue tone to prevent the user from falling asleep.

The full DSP mathematics and filter coefficients are compiled directly into the safe Rust/WASM audio kernel executing in the browser's AudioWorklet thread.