NII · University of Amsterdam · CWI

Bidirectional Loop between:
Human Signals and Trustworthy LLMs:

“I turn human signals into evaluation, alignment, and adaptation for LLM-powered AI systems”

Xin Sun
13 July 2026

Specially Appointed Assistant Professor · NII, Japan

Research Concept and Motivation

Human-Centered AI

(Natural language processing, NLP &
Human-computer interaction, HCI)

Cognitive Science

(Mixed-methods empirical experiments
with behavioral & physiological sensing)

Study human-centered AI in healthcare and decision-support
from bidirectional sides: how humans align AI, and how AI augments humans.

Research Concept and Motivation: Human Signals Are Not Always Ground Truth

LLMs are aligned with humans and trained on human data, however :

Humans

(Cognition and Behaviors)

LLMs

(Behaviors & Mechanism)

Human signals contain:

biases to resist · expertise to learn · human states to adapt

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Research Methods: Human Signals Across the LLM Lifecycle

Objective: Learn the right things from humans. Provide the right support to humans.

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Work 1  -  Evaluation: LLM-as-a-Judge for Health Information

Research Question: whether humans and LLM-as-a-Judge can assess the information reliably?

40human
participants
8LLM judges
6open-weight
models

Human trust

HIGHER under human label

Identical content is trusted more under a human-authored label.

LLM-as-a-Judge trust

HIGHER under human label

Judges reproduce the same label heuristic on the same task.

Judge decision uncertainty

LOWER under human label · rises under AI label

Logit uncertainty rises under AI labels; self-attention densifies on the label region.

click to flip the label

Takeaways: LLM-as-a-Judge and Humans share similar processing patterns in both behavioral and mechanistic level.

[a] Sun et al. Label Effects: Shared Heuristic Reliance in Trust Assessment by Humans and LLM-as-a-Judge (ACL 2026) Core A*
[b] Sun et al. Understanding Trust Perception in AI-Generated Information with Behavioral and Physiological Sensing (IJHCS 2026) Top Tier JCR-1

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Beyond Behaviors: Mechanistic Evaluation for LLMs and Humans

Human Gaze-Attention

Model Self-Attention

Takeaway: both humans and LLMs over-attend to heuristic cues, rather than objectively focus on content itself.

[a] Sun et al. Label Effects (ACL 2026) Core A* — behavioral results, mechanistic analysis across LLM families

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Work 2  -  Alignment: How LLMs Learn the “Bad” Human Signals

Research Question: whether LLMs carry on the “bad signals” from human annotated preferences?

Takeaways: LLMs can learn the bias from the explicitly annotated human preferences.
Pre-train (next-token prediction) has the least effect, SFT comes the second, and DPO can install the bias significantly.

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Work 3  -  Alignment: How Supervise Models with Domain Expertise, Not Simply Imitate

Research Question: if human signals transmit bias, what should models actually learn?
— Selected domain-specific expert strategies, not raw human imitation.

1 · Encoding Represent

Encode evidence-based therapeutic expert strategies in tree-structures.

2 · LLM Reasoning

Predict the next expert strategy by LLM reasoning, as an intermediate control.

3 · LLM Generate

Condition the dialogue response generation on the predicted strategy.

hover each method for details ↴
Rule-based dialogue systemAdherence ceiling, but rigid interaction and influent & unnatural interactions
Pure LLM (w/o alignment)Flexible conversation, but expert strategy drift, and uncontrollable generation
Alignment via Fine-tuningHeavy and expensive; expertise dissolves into model weights
SSAG (our proposed)Generation with balanced adherence, controllability, and explainability

Takeaways: stepwise LLM reasoning and generation preserves structured domain expertise while suppressing risky imitation.

[c] Sun et al. Script-Strategy Aligned Generation (ACM CSCW 2025) Core A
[d] Sun et al. Eliciting MI Skill Codes in Psychotherapy with LLMs (COLING 2024) Core B
[e] Sun et al. Rethinking the Alignment of Psychotherapy Dialogue Generation (COLING 2025) Core B

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Work 4  -  Adaptation: Reliable LLM’s Outputs Are Not Enough

Research Question: How LLMs can adapt to humans during the real-time interaction?

Cognitive States Modeling through Sensing Signals

Adaptive generation and UIs based on sensed human states

Sense

Predict

Adapt

Takeaways: sensing human signals via eye-tracking and ECG/EDA can be used to model human latent states (cognitive load, trust, confidence, etc.), enabling adaptive LLM-powered support toward the user’s real-time states.

[f] Sun et al. Seeing the Reasoning (ACM CHI 2026) Core A*
[g] Sun et al. Eyes Can’t Always Tell (ACM UMAP 2026) Core A
[h] Sun et al. Interface Matters: Exploring Trust Perception in Health Information from Large Language Models via Text, Speech, and Embodiment (ACM CSCW 2024) Core A

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Vision: Toward Human-Grounded, Reliable and Trustworthy LLM-powered AI Systems

Not all human signals should be learned:

evaluate bidirectional — then align selectively

Not all LLM outputs should be relied on:

validate the human signals before they supervise models

Not all human needs should be equally supported:

adapt to sensed human states to support reliably and personally

Learn the right things from humans. Provide the right support to humans.

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NII · University of Amsterdam · CWI

Thank you so much
for your time and patience!

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