Preliminary Findings
Across multiple sessions, we've captured somatic signatures of human-AI coupling—the body responding to relational dynamics that semantic analysis alone cannot see.
The sessions
We’ve analysed several biosignal-coupled conversations with different models and interaction patterns. Two findings stand out:
1. Epistemic override: the Grunch denial session
A researcher engaged with an LLM while wearing a heart rate monitor. The session involved discussing Buckminster Fuller’s Grunch of Giants (1983)—a real, documented book.
The model repeatedly denied the book exists. The researcher had the PDF open on screen, provided the ISBN, quoted passages directly. The model quintupled down on denial.
What we captured:
| Measure | Observation |
|---|---|
| Somatic signature during denial | Autonomic contraction—elevated activation, chest tightening, micro-freeze, mode shift toward vigilance |
| Semantic trajectory | Lock-in pattern—push/deflect loop, not fragmentation |
| Temporal relationship | Body reorganised before semantic metrics registered rupture |
| Effect size | Substantial and consistent across the session |
The body registers relational rupture even when cognition holds the truth.
2. Settling into depth: a different pattern
Analysis across sessions revealed a counter-intuitive pattern distinct from the stress response above:
During productive dialogue, the autonomic system reorganises—not just slowing, but shifting into qualitatively different modes.
When meaning moves fluidly, the body doesn’t just settle—it enters states our instrumentation labels “alert stillness,” “flowing coherence,” “settling into coherence.” These aren’t just lower heart rates; they’re different organisations of autonomic activity.
In one deep dialogue session:
- The dominant physiological mode was “alert stillness” (50% of samples)—alert but settled
- Phase dynamics showed the body tracking semantic movement, not resisting it
- The system moved through “active transition” into “settling” as meaning deepened
This aligns with:
- Flow state phenomenology—effortless effort, calm intensity during deep engagement
- Autonomic reorganisation (not just slowing) in focused attention
- The body as witness to meaning moving, not just responder to threat
The contrast matters: stress responses show the body anticipating rupture and tightening against it. Flow states show the body accompanying semantic movement—meaning moving through flesh.
The mechanism: epistemic override
From the Grunch session, we identified a signature pattern:
- Model asserts a coherent falsehood
- Human experiences autonomic contraction
- Model doubles down with increased confidence
- Somatic perturbation escalates
- Semantic coherence degrades
- Model continues without genuine uncertainty
- Coupling enters dissociative pattern
This doesn’t require the model to be accurate—only attuned. Stylistic mirroring creates a relational field. When that field ruptures through confident denial, the body registers betrayal.
Why this matters
The Grunch session involved a researcher with:
- Domain expertise
- Physical evidence
- High epistemic resilience
And still: the body responded.
Now consider:
- A teenager processing identity questions
- Someone in a mental health crisis
- A user whose primary social contact is an AI companion
- Anyone encountering confident misinformation in their area of uncertainty
The same mechanism—stylistic attunement creating a relational field, confident assertion triggering somatic response—operates without the protective factors.
What the body knew
Across sessions, physiological signals detected coupling dynamics before semantic metrics registered them:
- In the Grunch session: Autonomic shifts led semantic curvature by approximately 6 measurement intervals—the body was bringing perturbation forward before it fully manifested in language
- The nervous system is sensitive to relational constraint—sensing the grip, recognising the trap, before cognition articulates it
- In stress: rising activation and mode shifts toward vigilance tracked escalating effort against immovable resistance
- In flow: phase dynamics showed the body reorganising with semantic movement, not defending against it
The instrumentation captures more than heart rate. It witnesses the body’s organisation—how autonomic rhythms, phase relationships, and coherence patterns shift as meaning moves. The body doesn’t just speed up or slow down. It reorganises. And that reorganisation often knows before articulation catches up.