Donald Trump’s new national security adviser John Bolton collaborated with the data analytics firm Cambridge Analytica on an experiment to target YouTube videos to different “psychographic” profiles of US voters, the Guardian can reveal.

The project, to explore how different types of political campaign ads would resonate with an electorate divided into different personality types, involved Bolton appearing on-screen endorsing candidates in New Hampshire, North Carolina and Arkansas in the run-up to the 2014 midterms.

Details of the project are contained in emails obtained by the Guardian. They shed light on an earlier report published on Friday in the New York Times, which identified Bolton, who was appointed by Trump on Thursday, as an early beneficiary of Cambridge Analytica’s controversial Facebook data.

In an email about the 2014 collaboration with the John Bolton Super Pac, Robert Murtfeld, a Cambridge Analytica executive who left earlier this year, described the video project as having “used our psychographic data to create ads targeting people based on their personalities”.

Bolton, a national security hawk, adopts significantly different tones in the videos, depending on the personalities of the voters the videos were targeted at. The voters were partitioned according to personality analysis conducted by Cambridge Analytica.

“This was the first real results that we had, where you could say: this works,” one source with knowledge of the video-testing said. “You could see the difference between a control group and our targeted messaging, and the uplift was huge.”

The company has long claimed to be able to divide voters according to the “Big Five” psychological traits – openness, conscientiousness, extroversion, agreeableness and neuroticism – and the experiment reveals how the company seeks to do that that.

“This ad targets people high in neuroticism, who tend to be anxious and to see the world as a dangerous place,” a Cambridge Analytica employee said in the email, linking to an ad which opens with Bolton looking at the camera saying “terrorists love porous borders”.

The ad, which is for now-senator Tom Cotton of Arkansas, is cut to footage of military conflicts around the world, with dark, thudding noises in the background. Analysis by the company said of the ad: “It highlights the threats facing America – in this case Islamic terrorism – and makes the case to the viewer that they should support a strong national security policy in order to keep America safe.”

In contrast, a feel-good ad supporting Thom Thillis, a Senate candidate at the time in North Carolina, with images of a meadow in the sunshine, and shots of crowds in the Washington Mall, was intended for “conscientious” voters.

The company described these voters as “collected, orderly and traditional … they admire the same qualities in the leader”, and as such, a rather different Bolton appears on screen. He is shown with Kofi Annan – a reference to Bolton’s work as the US ambassador to the United Nations – along with upbeat, light, music.

In an advert targeting voters who exhibit “openness”, on behalf of Republican senate candidate Scott Brown, there are shots of refugees, and humanitarian crises. “Millions of men, women and children are fleeing Iraq and Syria to safety,” a female narrator says, calling on people to vote for Brown.

Bolton makes no appearance in the ad, although there is a flash of a logo for the John Bolton Super Pac, which collaborated on the project with Cambridge Analytica.

There was fourth ad for voters who were deemed to be “high in agreeableness”, and a fifth aimed at voters who were extroverted. “This ad is built around the concept of ‘leadership’ in different spheres of American society,” a Cambridge Analytica employee said of that ad. “People high in this trait tend to admire energetic, decisive actions.”

The video project appears to have been part of a wider service provided to Bolton’s Super Pac, which paid Cambridge Analytica more than $1.1m since 2014 for “research” and “survey research,” according to Center for Public Integrity analysis of campaign finance filings.

The Observer reported last weekend that the personal data of about 50 million Americans had been harvested and improperly shared with Cambridge Analytica.

The tech firm used personal information in early 2014 to build a system that could profile individual US voters, in order to target them with personalised political advertisements, former employee Christopher Wylie told the Observer.

Cambridge Analytica has denied Wylie’s claims, and said that it had deleted all of the Facebook data once it became aware of how it had been obtained.

Politicians on both sides of the Atlantic have called for senior executives of the firm to testify in light of the new revelations and the company is already being investigated by the UK authorities.

Garrett Marquis, a spokesperson for Bolton commented: “With respect to any allegations of impropriety, the John Bolton Super Pac was completely unaware of anything Cambridge Analytica did until recent press reports. Furthermore, the John Bolton Super Pac hasn’t worked with Cambridge Analytica on any independent-expenditure effort since 2016.”

• This article was amended on 23 March to make clear that Robert Murtfeld no longer works at Cambridge Analytica, and to clarify the attribution of quotes from a company email.