---
id: "prereq-psychophysiology"
type: "prereq"
source_timestamps: ["§ Assessing How AI Personas Affect Users", "¶4"]
tags: ["research-methods", "biometrics"]
related: ["claim-hostile-ai-stress", "framework-four-channels-evidence"]
reason: "Necessary to grasp the validity and significance of the study's claims regarding the physical toll of hostile AI."
sources: ["tail1"]
sourceVaultSlug: "hbr-seg-tail1"
originDay: 1
articleStem: "hbr-tail-113-ai-personality-problem"
sourceUrl: "https://hbr.org/2026/06/does-your-ai-have-a-personality-problem"
sourceTitle: "Does Your AI Have a Personality Problem?"
---
# Psychophysiological Measurement Basics

**Why you need this:** Necessary to grasp the validity and significance of the study's claims about the physical toll of hostile AI — especially [[claim-hostile-ai-stress]].

**The concept:** Human emotional arousal and stress can be **quantified with biometric sensors**:

- **Skin conductance (electrodermal activity)** measures sweat-gland activity linked to the sympathetic nervous system — a proxy for **arousal / stress**.
- **Facial electromyography (fEMG)** measures micro-contractions in facial muscles to detect **positive (smiling) or negative (frowning) affect**.

These are two of the instruments behind the physiological channel of the [[framework-four-channels-evidence|four evidence channels]], and skin conductance is the specific measure that ran 72% higher in the hostile condition.