One day several years ago Valorie Salimpoor took a drive that would change the course of her life. She was at the peak of what she now calls her “quarter-life crisis,” not knowing what kind of career she wanted or how she might use her undergraduate neuroscience training. Hoping an outing might clear her head, that day she jumped in her car and switched on the radio. She heard the charging tempo and jaunty, teasing violin of Johannes Brahms’s Hungarian Dance No. 5.