Now, after a computer analysis of three decades of hit songs, Dr. DeWall and other psychologists report finding what they were looking for: a statistically significant trend toward narcissism and hostility in popular music. As they hypothesized, the words “I” and “me” appear more frequently along with anger-related words, while there’s been a corresponding decline in “we” and “us” and the expression of positive emotions.

“Late adolescents and college students love themselves more today than ever before,” Dr. DeWall, a psychologist at the University of Kentucky, says. His study covered song lyrics from 1980 to 2007 and controlled for genre to prevent the results from being skewed by the growing popularity of, say, rap and hip-hop.
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Some psychologists are skeptical that basic personality traits can change much from one generation to the next (or from one culture to another). Even if students are scoring higher on the narcissism questionnaire, these skeptics says, it may just be because today’s students are more willing to admit to feelings that were always there.

Dr. Twenge acknowledges that students today may feel more free to admit that they agree with statements on the questionnaire like “I am going to be a great person” and “I like to look at myself in the mirror.” But self-report bias probably isn’t the only reason for the changing answers, she says, and in any case this new willingness to brag is in itself an important cultural change.

[I love myself, I think I'm grand ...]