Frequently Asked Questions
Questions about ad testing and EchoDepth
From the science behind FACS and VAD scoring to pharma research applications, culture measurement, GDPR compliance and how to get started. For deeper reading, see our Insights articles and Glossary of terms.
Ad testing
What is ad testing?
Ad testing shows an ad to a sample of people from its target audience before or after launch to find out how it works. Pre-testing happens before the media spend, so you can choose between edits, fix weak moments or drop an ad that doesn't land. EchoDepth pre-tests ads by measuring viewers' facial response second by second, alongside a short survey.
How does facial coding work for ads?
Each viewer watches the ad on their own webcam. Software detects the face on every frame and scores the facial muscle movements defined in the Facial Action Coding System (FACS), such as AU12, the lip-corner pull of a smile. EchoDepth turns those Action Units into valence, arousal and dominance, then averages across viewers to give a response curve for every second of the ad.
Is facial coding accurate?
Automated coding of Action Units is well established, and peer-reviewed work has found that automatic facial coding of people watching commercials relates to their own ratings of the ads and brands. But a facial expression is not a direct readout of a feeling, and people watching alone often show subtle expressions. That is why EchoDepth reports results across many viewers, with the Action Unit detail behind each score, and pairs it with a survey. The UK ICO has warned that emotion AI can be immature, so we publish our method and its limits.
How many viewers do I need to test an ad?
EchoDepth recommends 15 or more viewers per audience segment for each ad or edit. Every group you want to report on separately, such as under-35s and over-35s, is its own segment and needs its own 15. We agree the sample with you based on your audience and the decision you need to make.
What is the Cavefish Emotional Index (CEI)?
The Cavefish Emotional Index (CEI) is a 0 to 100 score of how people feel, read directly from what they write or say. It is the average of five readings, each 0 to 100 where higher is healthier: Advocacy, Goodwill, Engagement, Drive and Assurance. Scores fall into four bands: Strong (80+), Good (60–79), Watch (40–59) and Act (below 40). In an ad test, the CEI is read from what viewers say and write about the ad after watching. It is separate from the Emotional Response Curve, which shows second by second what their faces did.
More detail: how an ad test works and our methodology, the response curve and the CEI.
About EchoDepth Insight
What is EchoDepth Insight?
EchoDepth Insight is a remote research and product testing platform that captures emotional response in real time using facial FACS analysis and VAD scoring. A participant opens a browser link on their own device, consents, and views the stimulus while the platform scores 44 facial Action Units per frame, converts them to valence, arousal and dominance, and plots the Emotional Response Curve against the stimulus timeline. No hardware, facility or specialist operator is required, so a study can run across several countries in a week. It is used for concept and packaging testing, advertising pre-testing and pharma communications research, with consenting research participants. Workforce measurement uses the separate text-based product, EchoDepth Signal, because inferring emotion from biometric data in a workplace is prohibited under EU AI Act Article 5(1)(f), and employee consent does not lift that prohibition.
What are the weaknesses of traditional product testing that EchoDepth addresses?
Traditional research methods suffer from social desirability bias (participants say what they think researchers want to hear), the articulation gap (people cannot accurately describe emotional responses), post-rationalisation (conscious reflection distorts emotional memory), peer pressure in group settings, recall bias, geographic limitations, and the absence of moment-to-moment emotional data during stimulus exposure.
What research use cases does EchoDepth Insight support?
EchoDepth Insight supports pharmaceutical patient research, HCP engagement studies, drug messaging testing, FMCG product and packaging testing, concept and idea evaluation, advertising pre-testing with second-by-second emotion curves, healthcare communication research and device usability studies.
Who does EchoDepth Insight work with?
EchoDepth Insight works with pharmaceutical companies, healthcare organisations, FMCG brands, research agencies and innovation teams who need to understand genuine emotional response — not just what research participants say they feel.
The science — FACS and VAD
What is FACS and why does it matter for research?
FACS (Facial Action Coding System) is the scientific gold standard for facial expression analysis, developed by Paul Ekman and Wallace Friesen. It maps every visible face movement to one of 44 numbered Action Units. Because AUs are largely involuntary — many cannot be consciously faked — they provide a reliable measure of genuine emotional response, independent of what the participant says or believes they felt.
What is VAD scoring in the context of research?
VAD stands for Valence (positive to negative), Arousal (calm to excited) and Dominance (submissive to in-control). EchoDepth Insight outputs continuous VAD scores throughout a research session, providing a three-dimensional emotional profile at every moment of stimulus exposure — not a single rating at the end.
How does a remote EchoDepth Insight session work?
Participants join via any device with a standard webcam or front-facing camera — no app installation required. Consent is captured digitally. Stimuli are delivered in-session: concepts, packaging, messaging, video or interview questions. EchoDepth captures 44 facial Action Units continuously throughout the session. VAD scores are computed in real time. Key moments are flagged automatically. A structured report is generated with emotion timelines, group aggregates and segment comparisons.
Pharma and healthcare research
How does EchoDepth Insight work for pharma research?
EchoDepth Insight captures moment-to-moment emotional responses in patient interviews, HCP discussions, clinical trial participant sessions and drug marketing material testing. It detects genuine emotional reactions to messaging, packaging, brand and product concepts — without relying on articulation or post-session recall.
Can EchoDepth Insight be used for patient journey research?
Yes. EchoDepth Insight is particularly valuable for patient journey research because it captures the emotional response at diagnosis communication, treatment decision points, therapy adherence interviews and care experience evaluation — all moments where patients are unlikely to accurately articulate their true feelings.
Is EchoDepth Insight suitable for HCP (healthcare professional) research?
Yes. HCPs are a notoriously difficult research audience — their professional training makes them highly effective at managing their self-presentation. EchoDepth Insight captures the involuntary physiological signals that reveal genuine response to product messaging, clinical data presentation and brand positioning.
How does EchoDepth Insight improve FMCG product testing?
Traditional FMCG research is distorted by the "interesting but wouldn't buy" gap — participants give safe social responses in group settings. EchoDepth Insight captures involuntary physiological response at the moment of stimulus exposure, revealing which concepts generate genuine desire versus polite curiosity. It supports packaging concept testing, brand evaluation, new product introduction research and advertising pre-testing.
Privacy, Ethics & Data
Is EchoDepth Insight GDPR compliant?
Yes. EchoDepth processes video in memory — no raw footage is stored. Only VAD scores and Action Unit activations are output. All processing is GDPR-compliant by design. Sessions are consented and time-bound with full participant data control. On-premise deployment is available for organisations with strict data residency requirements.
Does EchoDepth claim to detect lies?
No. EchoDepth does not claim to detect deception. It measures involuntary physiological markers — facial Action Units and VAD states — during consented research sessions. All interpretation and recommendation decisions remain with qualified researchers and client teams. This distinction is fundamental and non-negotiable in all deployments.
How does EchoDepth handle sensitive pharma research data?
No raw video is retained. Only VAD scores and Action Unit activations are output and stored. All sessions require explicit participant consent. On-premise deployment is available for organisations with strict data residency requirements. GDPR-compliant by design.
Company & Team
Who is behind EchoDepth Insight?
EchoDepth Insight is built by Cavefish, a Cardiff, Wales-based emotional AI company founded in September 2023. The platform is built on ISO 9001 and Cyber Essentials certified infrastructure. Cavefish is an FCA Regulatory Sandbox participant and has received 13 industry awards.
Who founded EchoDepth Insight?
EchoDepth Insight was founded by Jonathan Prescott, who previously led digital performance and behavioural analytics teams at the Royal Mint and Assurant. He holds an MBA from Bayes Business School and a B.Eng in Computer Systems Engineering. He is Strategy Director of AI Wales CIC and a Data & AI Council member at Technology Connected Wales.
What is Cavefish's approach to responsible emotional AI?
EchoDepth Insight does not diagnose individuals or claim to read minds. It measures Valence, Arousal and Dominance states during consented, time-bound research sessions. All interpretation and recommendation decisions remain with qualified researchers and client teams. No raw video is retained. Cavefish will not deploy EchoDepth in contexts where demographic bias could produce discriminatory outcomes.
See also: EchoDepth vs iMotions · EchoDepth vs Culture Amp
How EchoDepth compares
Getting started
How do I get started with EchoDepth Insight?
Contact us to book a 30-minute discovery call. We will explore your research challenge and constraints, then provide a live demo or sandbox API access depending on your needs. Every enquiry is read by a human and we respond within one business day.
Can EchoDepth Insight be used for advertising testing?
Yes. EchoDepth Insight provides second-by-second emotional curves across video advertising — showing exactly which moment lands, which triggers concern, and where attention drops. It supports both pre-testing before campaign launch and post-campaign emotional shift measurement against baseline.
People & Culture
Full culture measurement methodology →Still have questions?
Book a 30-minute discovery call. We'll walk through your research challenge and show you what emotional capture looks like in practice.