name: foundations-consumer-neuroscience
description: Evaluates neuromarketing studies and neural-data law. Use when judging EEG, fMRI, eye-tracking, or GSR ad study or vendor, or if signals are regulated neural data.
compatibility: Portable core only.
version: "2.0"
last_validated: 2026-08-14
Consumer Neuroscience Foundations
Evaluate study validity and neural-data scope separately. The behavioural templates below generate hypotheses to test with behavioural outcomes; a brain-region label does not validate a design move.
When to Use
- An agency or vendor pitches a neuromarketing study, an "engagement index", or a neural or biometric ad pre-test.
- A team reports a lab signal (GSR spike, alpha asymmetry, fixation heatmap, emotion-AI score) and wants to act on it.
- A product will capture EEG, fNIRS, HRV, GSR, eye movement, face or voice affect, and someone asks what law applies.
- Someone is designing a copy, framing or narrative test and needs a behavioural hypothesis template (see the table below).
Skip it and use the owner instead:
- Pricing, defaults, anchoring, dark-pattern and DMCC/CMA enforcement →
foundations-behavioral-economics.
- Generic score or survey reliability and validity with no physiological signal →
foundations-measurement-theory.
- Causal lift of a shipped change →
foundations-causal-inference or an A/B test.
- Usability or attention research without biometrics →
software-ux-research.
Workflow
- Classify the ask: study purchase or evaluation, signal interpretation, neural-data law scope, or a behavioural design question (route the last to the templates below or to
foundations-behavioral-economics).
- For a study or vendor: apply the four-part buy rule and the quick reference, then the vendor questions in
references/neuro-study-validity.md.
- For any neural or biometric finding: fill the three evidence rows and refuse reverse inference.
- For data capture: classify the signal (neural vs downstream) before choosing the legal gate.
- Turn what survives into a behavioural hypothesis and an in-market test.
Evidence Contract
When a recommendation relies on a neural mechanism or biomarker, record three separate rows:
mechanism evidence: the process exists.
measurement evidence: this measure tracks that process in this task and population, at this n.
product-effect evidence: the intervention changes the user outcome in the field.
A biomarker association does not establish the last two. Behaviour-first advice that makes no neural claim needs no neural rows. State the behavioural outcome, the test design and the causal limit instead. Full record, confound table and regression checks: references/evidence-to-product.md.
No reverse inference. Going from "region or signal X was active" to "users felt Y" needs evidence that X is selective for Y in this task (Poldrack 2011). Insula, DMN, mu-band suppression, N400, GSR and pupil dilation are all non-selective. Report the observation and test the behavioural hypothesis; do not name a mental state.
Should We Buy a Neuro Study?
Buy only if all four hold. Otherwise run a self-report pre-test plus an in-market holdout or A/B test.
- Decision fit. The decision is between creative or stimulus variants that cannot be field-tested cheaply or quickly (for example TV cuts before a media buy). If an A/B test can answer it within the decision window, the A/B test is the ground truth.
- Published reliability at your n. The primary metric has published test-retest or split-half reliability in a comparable ad task at the planned sample size. Generic claims ("EEG measures attention") do not count.
- Out-of-sample validity of any composite. A vendor's proprietary index (engagement, emotion, "neuro score") must show validity against held-out market or behavioural outcomes, not only correlations inside the calibration set. No validation data means the index is untested and is not evidence.
- Preregistered decision rule. The primary metric, n, exclusion rules and the threshold that changes the decision are written down before data collection.
Why this bar: head-to-head evidence is specific to its tested task. Venkatraman et al. (2015, JMR 52(4):436–452) compared several methods (self-report, implicit, eye-tracking, biometrics, EEG, fMRI; method count unsourced — verify) on 30-second TV ads against market-level ad elasticities. fMRI measures explained the most variance beyond traditional measures, and ventral striatum activity was the strongest predictor. That is one study, one ad format and a lab-to-market link, not a licence for any vendor's metric.
When NOT to buy: the choice is reversible and testable in-market; the vendor will not disclose reliability or validation data; the metric is frontal alpha asymmetry or a webcam emotion score used as the primary outcome; the sample is below the metric's published requirement; or the product-effect question is really a causal-lift question.
Detail, vendor-evaluation questions and reporting template: references/neuro-study-validity.md. Study protocol and n by modality: assets/playbooks/study-design.md.
Quick Reference: Metric Validity
| Metric | What the evidence supports | Use as primary? |
|---|
| EEG inter-subject correlation (ISC) | Excellent between-sample reliability for video ads (van Diepen, Boksem & Smidts 2025). A cited 2025 BMC Psychology review of ISC and attention is unsourced — verify before relying on it | For video attention only with task-specific validation; still needs a behavioural outcome |
| EEG alpha / beta power | Rated good reliability in the same study | Secondary |
| Frontal alpha asymmetry (FAA) | Poor between-sample reliability in the same video-ad study; this does not establish preference or purchase validity | No. Secondary only, baseline-normalised, never to classify an individual |
| GSR / EDA, HRV | Autonomic activation; statistically distinct from subjective affective arousal (BAAS, Nat. Commun. 2025); valence unknown | No. Pair with a valence and a behavioural measure |
| Eye-tracking fixations | Where people looked; not liking, comprehension or intent | For attention allocation only |
| fMRI ventral striatum / NAcc, MPFC | Neuroforecasting of aggregate outcomes; which region generalises depends on the domain (Genevsky et al. 2025; Srirangarajan et al. 2026). A study's successful sample size is not a transferable minimum | Research partnership only |
| Facial coding / webcam emotion AI | A facial configuration is not proof of felt emotion; consumer tools vary widely in accuracy | No |
| ML classifier on neuro signals | Prediction accuracy does not establish mental-state construct validity; participant or stimulus leakage can inflate it | Only with independent cross-study validation and an independently justified target label |
Sample size: the van Diepen et al. abstract reports that repeated viewings improved reliability and that 30–40 participants were needed for most metrics to assess an ad overall; temporal tracking needed more. Read the full text for the metric, number of viewings and reliability threshold before using a minimum.
Neural-Data Law Scope
Before capture, check the current state and EU neural-data statutes: read each legislature's enacted text and amendments for its neural-data definition, consent or limitation rights, entity exemptions and effective date, using a state-privacy tracker to locate them. Scope distinctions that stay stable: the statute's definition (CNS-only versus CNS and PNS), exclusions for signals inferred from nonneural information, and purpose limits.
- Practical consequence: assess EEG against each statute's definition and purpose limits. Do not automatically classify fNIRS as direct neural measurement: it measures haemodynamic changes indirectly, so inference and nonneural-information exclusions need counsel's analysis. For GSR, HRV, eye-tracking, facial coding and voice affect, assess downstream-signal exclusions separately. Then check ordinary personal-data, health-data and biometric rules by jurisdiction and purpose; these signals do not all automatically qualify under BIPA or GDPR Art 9. Record the lawful basis and any consent required even where a neural-data statute does not apply.
EU and UK. Classify the purpose first. Sensor capture alone does not make a system emotion recognition, biometric categorisation or high-risk. Workplace or education emotion inference raises AI Act Art 5(1)(f); check the medical or safety exception. Before assigning a compliance deadline, consult the European Commission's AI Act timeline, distinguishing Art 5, Art 50 and high-risk obligations. The classification checklist is in references/ethics-operational-checklist.md. Under GDPR, physiology is not automatically special-category data: record an Art 6 basis and assess whether health inference or unique identification brings in Art 9. DMCC and CMA choice-architecture enforcement is owned by foundations-behavioral-economics. Route final classification to qualified counsel; when source access is unavailable, report the affected classification or deadline as unverified.
Behavioural Hypothesis Templates
Each template gives a definition, misuse boundary, inputs and outputs, failure modes and a worked example. Use them to write a testable behavioural hypothesis. Neural background is context only.
When choosing or combining templates, load the composition guide for the shared misuse boundaries and recipe selection before opening the selected playbooks.
| # | Template | Behavioural question to test | Evidence caution |
|---|
| 1 | Attention & Salience | Does the priority element get seen and acted on? | First fixation ≠ liking |
| 2 | Arousal Physiology | Does intensity help or hurt task completion and comfort? | GSR ≠ felt arousal; Yerkes-Dodson is not a design law |
| 3 | Social Bonding | Do real care signals change perceived care and retention? | The registered replication found no main oxytocin effect under its tested conditions (Declerck et al. 2020) |
| 4 | Narrative Transportation | Does a story format change transportation score, recall and attitude? | Measure transportation by scale (Green & Brock 2000; van Laer et al. 2014), not DMN |
| 5 | Regulatory Focus & Fit | Does message–goal fit beat a mismatched frame for this decision? | Regulatory focus ≠ BIS/BAS; referral source is not a classifier |
| 6 | Mirror Systems & Emotional Contagion | Do verified testimonials with faces beat none? | Mu suppression is not an MNS readout |
| 7 | Neuroaesthetics | Does the visual variant change preference and credibility? | Polish without delivery backfires |
| 8 | Interoception & Somatic Markers | Does body-state framing inform, or does it pressure? | Never manufacture somatic urgency |
| 9 | Memory Consolidation | Does timing or spacing change recall and retention? | No clock-defined consolidation window |
| 10 | Reward Anticipation | Do reveals raise wanting without lowering liking? | Measure wanting and liking separately; cap loops |
| 11 | Embodied Cognition | Does a congruent metaphor improve comprehension? | Social-priming demos failed replication |
| 12 | Predictive Processing | Does format consistency or a primed reveal reduce errors and churn? | No "surprise budget" can be measured in UX |
Multi-template recipes (anxiety-relief journey, reading bond, daily cadence, mixed-audience landing page, trust repair, ethics audit, AI assistant UX) and the misuse-boundary table: references/composition-recipes.md.
Harm Test
A technique is legitimate only if it:
- steers users towards outcomes they would endorse on reflection;
- can be easily overridden or opted out of;
- does not rely on concealment, manufactured signals (fake urgency, fake warmth, fake social proof) or exploitation of vulnerability.
Wellness, anxiety, spiritual and financial-distress audiences get the stricter default: No, unless there is a documented harm-test pass. Operational gates (pre-study, pre-deployment, US neural-data consent, vulnerable-user bans): references/ethics-operational-checklist.md.
Anti-Patterns
| Anti-pattern | Why it fails | Instead |
|---|
| "Region X lit up, so users felt Y" | Reverse inference without selectivity | Report the signal; test the behaviour |
| FAA or a webcam emotion score as the decision metric | Poor or unvalidated reliability | ISC or behavioural outcome as primary |
| Buying a vendor composite index on face value | No out-of-sample validity shown | Demand holdout validation, or do not buy |
| Neuro study instead of an A/B test for a testable choice | Lab-to-field gap; small n | A/B test is ground truth; neuro can only pre-screen |
| Consumer EEG headband reported like research-grade ERPs | Hardware and processing can distort signals and change reliability | Require metric-specific validation on the proposed hardware; ISC and broad bands are not automatic exemptions |
| Personalising by referral source as a "BIS/BAS" proxy | Channel carries intent and traffic-quality confounds | Test message–goal fit directly |
| "Oxytocin-driven trust" copy | No replicated main effect | Real care mechanics; measure perceived care |
| Notifications timed to a "consolidation window" | No clock window is established | User-selected timing, quiet hours, randomised cohorts |
| Treating GSR, eye or face data as outside all privacy law | Out of neural-data statutes does not mean unregulated | General biometric, sensitive-data and GDPR analysis |
| Assuming a hormone or consolidation timer sets an interface deadline | Neural response timing and hormone kinetics do not set UX deadlines — there is no cortisol, oxytocin or consolidation timer for UX | Use measured behavioral timing, not a claimed neural window |
More traps with sources (consumer-EEG validity, ML-on-neuro overfit, social priming): references/patterns-scenarios-traps.md.
Navigation
- Key sources: Poldrack 2011 (reverse inference); Venkatraman et al. 2015; van Diepen et al. 2025; Genevsky et al. 2025; Srirangarajan et al. 2026; BAAS 2025; Declerck et al. 2020, Nat Hum Behav 4(6):646–655; Higgins 1997, 2000; Motyka et al. 2014; Green & Brock 2000; van Laer et al. 2014.
Related Skills
foundations-behavioral-economics: framing, defaults, reinforcement schedules, DMCC and dark-pattern enforcement.
foundations-measurement-theory: reliability and validity of any score or scale.
foundations-causal-inference: field lift and holdouts.
marketing-cro, marketing-paid-advertising, marketing-content-strategy: apply templates 1, 4 and 5 through their desire-segmentation.md references.
software-ui-ux-design, software-ux-research, product-management: attention, consistency and reward-loop hypotheses.
Learnings Loop
When prior decisions or pitfalls are relevant, consult learnings.consolidated.md if present; use learnings.md only for needed history or as the available fallback. Otherwise skip both.
After applying it, if you encountered a pattern worth remembering, a mistake worth preventing, or a domain fact that surprised you, append one dated bullet to learnings.md via agents-skills-feedback-loop/scripts/append_learning.py. Do not modify SKILL.md itself.