All those hours practicing the piano pay off big time by biologically enhancing a person's ability to quickly recognize and mentally process sounds that carry emotion, according to a new study.
The study, from Northwestern University in Evanston, Ill., offers a new line of evidence that the brain we end up with is not necessarily the same brain we started out with.
"We are measuring what the nervous system has become, based on an individual's experience with sound," Nina Kraus, director of the university's groundbreaking Auditory Neuroscience Laboratory, said in a telephone interview.
Kraus and a team of researchers attached electrodes to the heads of 30 people, half of whom were serious musicians and half of whom had no significant musical training. The electrodes measure electricity, "which is, of course, the currency of the nervous system," Kraus said. The study revealed two major differences between the musicians and the nonmusicians.
Musicians heard an emotion-packed, complex sound with an enhanced sensitivity, and they also were less distracted by simple sounds, according to the study, published in the current issue of the European Journal of Neuroscience.
"What we found in this study is both an enhancement and an economy of resources varies as a function of the extent of musical experience," Kraus said. "The more years the person has been playing an instrument, and the earlier the person began musical training, the larger the effect."
Although many other studies have tried to show the beneficial effects of musical training, the researchers said their findings "provide the first biological evidence for behavioral observations indicating that musical training enhances the perception of vocally expressed emotion." The findings have implications far beyond the world of music.
"The same neural transcription process that is enhanced in musicians is found to be deficient in some children with language disorders such as dyslexia and autism," Kraus noted.
The research suggests that something as basic as musical training may be a useful therapeutic device, along with other more traditional techniques.
"Quickly and accurately identifying emotion in sound is a skill that translates across all arenas, whether in the predator-infested jungle or in the classroom, boardroom or bedroom," said Dana Strait, a doctoral candidate in the music department and lead author of the study.
The researchers relied on an emotion-packed sound that has been used for many years by scientists around the world who have studied auditory processes -- the sound of an infant crying. That sound carries an enormous emotional load, but it is also a surprisingly complex sound.
Sound waves measured during the experiment show periods of relatively mild emotional content in the sounds from the baby -- almost a straight line on a chart -- punctuated with brief bursts of complex sounds that vary in intensity, frequency and strength.
The participants, wearing earphones, sat in front of a monitor showing nature films with subtitles. Every now and then, they heard the sound of a baby crying through the earphones. The electrodes measured the stimulus -- the baby crying -- and the response of each participant.