Choirs synchronize not only their voice but also their heartbeats, according to a new study.
Researchers in Sweden found that the pulse of the singers in the choir tends to increase and decrease in unison.
The study looked more generally at how music affects our body and our health. Researchers were looking for ways in which music could be used to heal.
One of the findings was that the hearts of singers begin to coalesce depending on the musical structure.
The study looked at 15 high-school students.
The group was asked to perform three different choral exercises: monotone humming, singing the well-known Swedish hymn "Harlig ar Jorden" (Lovely is the Earth) and chanting a slow mantra.
The students' vitals were recorded while they sung.
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"Singing regulates activity in the so-called vagus nerve which is involved in our emotional life and our communication with others and which, for example, affects our vocal timbre," said study author, Bjorn Vickhoff, in a statement.
"Songs with long phrases achieve the same effect as breathing exercises in yoga. In other words, through song we can exercise a certain control over mental states."
The key is timing and breathing and the activation of the vagus nerve that lowers the heart rate.
Researchers believe that songs, like breathing exercises, can help control the heartrate via the breath. The next step is to see whether singing in unison can also help people to connect mentally and collaborate.
The findings were published in the journal Frontiers in Neuroscience.