> ## Documentation Index
> Fetch the complete documentation index at: https://docs.medera.info/llms.txt
> Use this file to discover all available pages before exploring further.

# Negative Valence Systems

> acute_threat_fear · potential_threat_anxiety · sustained_threat

| Construct                  | Description                                       |
| :------------------------- | :------------------------------------------------ |
| `acute_threat_fear`        | Immediate fear response to an identifiable threat |
| `potential_threat_anxiety` | Anticipatory response to uncertain threat         |
| `sustained_threat`         | Prolonged response to chronic stressor            |

Key contributors include vocal `f0_mean`, `jitter`, `vocal_anxiety_index`, facial `stress_index`, `hrv_lf_hf_ratio`, and assessment context (GAD-7).