think on this.

Over the past half-century, pop hits have become longer, slower and sadder, and they increasingly convey “mixed emotional cues,” according to a study just published in the journal Psychology of Aesthetics, Creativity and the Arts.

“As the lyrics of popular music became more self-focused and negative over time, the music itself became sadder-sounding and more emotionally ambiguous,” according to psychologist E. Glenn Schellenberg and sociologist Christian von Scheve.

Analyzing Top 40 hits from the mid-1960s through the first decade of the 2000s, they find an increasing percentage of pop songs are written using minor modes, which most listeners—including children—associate with gloom and despair.