For patients who already have dementia, music can be used in a different way to help the mind.
The emotional response that people get from listening to music, and the brain chemicals associated with pleasure that get released in the process, are distinct from the structural changes in the brain that playing music over time may instigate, scientists said.
Trends emerging from research show that music exposure -- whether through casual listening or more formalized music therapy -- can help reduce the incidences of behavioral issues and generally calm dementia patients, said Beth Kallmyer, vice president for constituent services at the Alzheimer's Association.
"Anecdotally what we hear is that people can be upset, even a little agitated, and when they're listening to music, even in the late stages, people can appreciate music," Kallmyer said.
Family members should help caregivers choose music that is meaningful to a person with dementia, she said. "The most important thing is keeping your interventions person-centered as much as possible."
Naomi Ziv of the Academic College of Tel Aviv Yaffo in Israel and her colleagues showed in a Journal of Music Therapy study that background music is associated with an increase in positive behaviors -- laughing, smiling, talking -- a decrease in negative ones, including aggressiveness and crying.
Music attracts attention; it also enhances focus and affects emotion, Ziv told CNN in an e-mail.
"When we hear familiar and preferred music, we mentally follow it," she said. "It seems that whereas general memory deteriorates in dementia, memory for music remains relatively intact."
Familiar or preferred music evokes memories and influences mood, which is perhaps the underlying reason for these results, Ziv said.
Catherine Shmerling appreciates the effect that certain musical events have had on her father, Dr. Sanford A. Shmerling, 85. The elder Shmerling used to be the medical director of the William Breman Jewish Home in Atlanta; now, he lives there. He has Alzheimer's, and most of his speech is not comprehensible, his daughter said.
On a recent weekend, a swing band performed at the nursing home. At first the former medical director sat in his wheelchair staring into space, but soon his daughter noticed him clapping his feet. She started swinging his arm with the music, and after a few minutes he gave her "a cute little smile."
"It's gratifying," Catherine Shmerling said. "There is something about -- I don't know, the music or the auditory or something -- that does seem to get past whatever it is that's blocking their normal communication, and somehow it gets in there."
Science may not have all the answers, but Shmerling savors these small signs that her father is listening.
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