Negative Valence Systems

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).