A new BYU study shows children as young as 5 months old can recognize upbeat melodies from a selection of drearier music; at 9 months, they can also pick out a sad song from a lineup of happy ones.

Research performed on 96 babies -- ages 3-9 months -- shows infants find ways of communicating or interpreting data before they can speak or understand words, similar to the way they understand intonation, but not vocabulary, said Ross Flom, a BYU psychology professor who served as the study's lead author.

"Babies are sensitive to emotion in a variety of domains and contexts, be it faces, voices and now, music," he said. "The melody is the message."

Although the infants clearly could not speak, experiments were run to help read what they say with their eyes. During this process, a neutral face is shown on a screen in front of the baby; music plays as long as the baby looks at the screen. The music stops as soon as the baby looks away. The longer the baby looks at the face, the longer the music plays, Flom explained. Based on his study's results, the happy music generally held the babies' attention three to four seconds longer than the sad music.

The picture of the neutral face was used to prevent bias that could lead subjects to look at the picture for longer or shorter periods of time, Flom said.

"You can't measure actual listening time, but you can compare what you're listening to and what you're looking at," he said.

Some of the most groundbreaking results from the study are challenges to perceptions that have been widely accepted by musicians for more than half a century, Iowa State professor and study co-author Douglas Gentile said. In 1956, musicologist and author Leonard B. Meyer theorized that music itself does not carry emotion with it, but people's reactions to it are based on individual emotions and preferences. The new study, however, shows music communicates its intrinsic emotions to listeners.

"We've been thinking about emotion in music all wrong since Meyer's 1956 theory," he said.

Anne Pick, co-author of the study and an emeritus professor in human development at the University of Minnesota, said there are limits to the study's findings.

"This should not be misinterpreted that there's a claim that infants experience the emotions, just that they can detect the difference between groups of musical excerpts that children and adults have judged to convey happiness and sadness."

Perception of moods in music was greater among the older babies. At 3 months of age, there seemed to be no recognition of different types of music. However, at 5 and 7 months, the babies were able to discriminate musically when playing a set of sad music followed by happy music. On the other hand, they did have more difficulty adjusting from happy to sad music. The subjects would eventually lose interest in the happy music, and when the sad music played, they had further entered a phase of boredom, Flom said.

Albert Yonas, a professor of child development at the University of Minnesota and an expert on infants' perceptual abilities, said he found the study fascinating, and wondered if results would differ among varied world cultures and music.

"I think it would be really interesting to know if this result would be true across all cultures, without using music from the Western world," he said. "Is it universal, or does it depend on what music the child has heard?"

Various factors, including cost, have made larger-scale studies difficult to perform, said Gentile. Although much remains unknown regarding musical interpretation on a worldwide level, several theories exist. One school of thought suggests music is a universal language. Another states the emotion one feels from music depends on one's culture and the music of that culture. A third hypothesis proposes listeners associate musical feelings with life experiences. For example, music may stir up memories of a loved one, or an experience that invokes either happy or sad emotions. All of the above theories have some level of truth in them, Gentile said.

A type of universal emotion in music is the soothing nature of lullabies. An example of cultural difference in music discrimination would be raaga music, which is popular in India. Gentile said Americans wouldn't know how to tell the difference between a happy raaga or a sad one.

An interesting side story to the study was how subjects' behavior changed while listening to the array of melodies. The infants would become more fussy or sad when sad music played, a phenomenon called "mood induction," Flom said.

Gentile said classical music was used primarily in the study, although the researchers also played a capella lullabies and jazz. Among the happy tunes heard were "Ode to Joy" from Beethoven's Ninth Symphony; one example of sad music was the second movement of his Seventh Symphony.

The results of the study will be published in the upcoming issue of the academic journal Infant Behavior and Development.