Advertising isn’t cheap — brands are predicted to spend a collective $757.44 billion on advertising by 2021. Understandably, they want a guarantee they’re getting their money’s worth, which is where startups like Spark Neuro come in.

Spark Neuro, a New York-based company founded in 2017, keeps a relatively low profile. But its star-studded lineup of investors includes actor Will Smith, former Disney CEO Michael Eisner, and prolific tech investor Peter Thiel, who along with five other investors today led a $13.5 funding round.

The startup’s secret sauce is an electroencephalogram (EEG) headset that evaluates electrical patterns in the brain. (The “Spark” in Spark Neuro stands for Scientific Persuasive Artistic Research-Driven Knowledge.) Data from it and other devices, including cameras that track gaze and facial expressions and electrodermal sensors, are fed into proprietary algorithms that determine as best they can a person’s emotional state.

“Spark Neuro’s approach to evaluating audience engagement is unique in that it combines brain and other nervous system activity to understand how people react to content accurately,” CEO Spencer Gerrol said in an interview conducted via email. “[Its] sophistication in measuring brain activity is unmatched. What is especially unique is that the data is processed and reported live in real time, requiring a powerhouse complex set of algorithms that clean noise from signal and process raw data into meaningful metrics.”

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Developing those algorithms was no easy task — Spark Neuro’s team of neuroscientists spent five years optimizing them — but they’re core to its analytics workflow. At least some of it was developed at Gerrol’s previous company, Spark Experience, which he sold to user experience research company Motive Design in 2016.

Here’s the gist: Spark pays focus group participants about $100 per session to strap on its suite of sensors and watch an advertisement, movie trailer, clip, or other pieces of content. Its system — taking into account more than 6,000 bits of information a second — charts their attention and emotion levels on a scale of 0 to 10.

Among Spark Neuro’s clients is a laundry list of Fortune 100 companies including Anheuser-Busch, Barclays, Clorox, FedEx, Fidelity, General Motors, JetBlue, Mars, State Farm, and Walmart. That’s in addition to Hollywood production houses like Universal, Paramount, and NBCUniversal, as well as the streaming video service Hulu.

Universal used the neuroanalytics platform to determine where people responded negatively to movie trailers, and NBCUniversal measured reactions to promotions and advertising among bilingual speakers for Telemundo. Hulu, meanwhile, employed it as an ad-sales tool, comparing viewers’ emotional responses to premium and regular ad sponsorships. And recently, Paramount became the first studio to conduct a test with a full-length movie: Darren Aronofsky’s Mother!

Gerrol said Spark Neuro’s infusion of fresh capital would be used to expand the business “both internationally and domestically.” It’ll open its first international office in Tokyo at the beginning of September, and it hopes to grow its headcount from 15 employees to 50 by the end of the year.

“Further strengthening their tech platform also creates the opportunity to transcend numerous industries, amplify new business models, and achieve immense scale,” Gerrol said. “Spark Neuro aims to be the dominating force in a still new neuro analytics industry.”

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