Humans also use short, staccato notes to arouse themselves, Snowdon said, and longer notes for calming purposes. You might tell a baby to calm down, for example, by saying "Aww, come on, come on," starting at a high pitch and descending, he said.
Frans B.M. de Waal, a professor of psychology at Emory University who studies primates, said the findings appear to say more about how monkeys respond to the sounds they make than they do about music or the evolution of music.
As to the idea that staccato sounds are perceived as more aggressive than softer sounds in both humans and the monkeys, de Waal said that may be the case in humans because lullaby-like music sounds similar to a mother's cooing voice.
Snowdon no longer has a monkey colony to use in his research. But he said his co-author, Teie, is exploring the concept of music for cats.
"If we understand how we can affect their emotional states through using musical tones and aspects of our speech, maybe those of us living with companion animals can have a better relationship with them, too," Snowdon said.
Visit the University of Wisconsin to hear the monkey music.
SOURCES: Charles Snowdon, Ph.D., professor, psychology, University of Wisconsin-Madison; Frans B.M. de Waal, Ph.D., professor, psychology, Emory University, Atlanta; Sept. 1, 2009, Biology Letters
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