Fifty years ago, the Beatles fired the first salvo in the British rock music invasion of America when they debuted on “The Ed Sullivan Show.” What better way to commemorate the broad reach of Beatlemania than to examine how much the Fab Four have invaded academic literature?

That’s just what Christopher King, a Thomson Reuters analyst and editor of the company’s ScienceWatch service, thought. He sifted through 12,000 journals and books, and turned up at least 500 articles with the word “Beatles” in the topic or title.

“We thought this would be a kind of interesting idea to do,” King said in a phone interview. “A fairly informal, light-hearted search, to find the impression they’d made.”

King collected the top 10 papers, based on numbers of citations, in a roundup for ScienceWatch.

In academic studies of the band, “there’s kind of this distinction between papers that centered on the Beatles themselves and an examination of their influence and place in history, and some that just seem to use Beatles music for the scientific subject at hand,” King says. “There are some papers in computer journals and audio engineering journals where they use Beatles tunes to refine [studies] of automated analysis, chord progression, melody, that sort of thing.”

The top paper on King’s list is a 1990 study from the journal Memory and Cognition. Researchers Ira Hyman Jr. and David Rubin asked 76 undergraduate students to recall Beatles’ songs after they were given titles and first lines of the tunes; another 704 undergraduates were given a line from a Beatles song and asked to name the title.

“The probability of recalling a line was best predicted by the number of times a line was repeated in the song and how early the line first appeared in the song,” Hyman and Rubin wrote. “Although the subjects recalled only 21% of the lines, there were very few errors in recall, and the errors rarely violated the rhythmic, poetic, or thematic constraints of the songs.”

The list also includes an in-depth analysis of the emotional cues in songs penned by Paul McCartney and John Lennon from 1962 to 1970 (the verdict: Lennon’s contributions were sadder, and the pair’s songs became less cheerful over time) and an analysis of Strawberry Fields, the John Lennon memorial in Central Park, “as a place of secular pilgrimage.”

King also found some interesting studies that didn’t make the list, because the Beatles music was not the main focus, but used or mentioned as part of a larger scientific goal. There was a psychology study where scientists tried to see if rats reacted differently to Beatles music versus Mozart pieces, and a case study in pediatric neurology of an infant whose epileptic seizures appeared to be triggered by Beatles music.

So, will the Beatles still be cropping up in science 50 years from today?

“I hope so!” King says. “You can see, even after a half-century their work is still being discussed. As long as people are interested in the cultural forces that shape society and how the world changes with regard to media and art, I would guess that they’d still be part of the discussion.”