When we describe doppel we often compare it to music. We say that like listening to music, a fast rhythm helps you to feel more alert, a slower rhythm is calming.
Most people can relate to this statement, many having experienced this effect before. There are all sorts of reasons why you might choose a particular song to get going or wind down - the melody, the lyrics, the memories you associate with it. But one thing you might not have realised is that the tempo of the song also changes how you feel.
But why does this happen?
Well, the link between heart rate and how a person is feeling is well known.
Have a think about this scenario: It’s dark. You hear a noise, you begin to feel scared, and your heart starts pounding. And now think about this one: It’s dark. You hear a noise, your heart starts pounding and you begin to feel scared. Which is true?
In reality, both are true. Your brain and body are constantly talking to each other with each other. The physiological state of the body which is encoded in the heart, among other body organs, is relayed to the brain constantly, on every single heartbeat. Our feelings and mood are influenced by our heart rate.
Returning to the example of music, recent research published in the BJM’s Open Heart journal found that underlying tempo of different types of music has an effect on heart rate and blood pressure.
Bernardi and colleague note that way back in 1920, it was Diserens who commented that music also had an effect on respiratory timing - he concluded that “in general respiratory rhythm follows that of the music”. They then go on to reference numerous studies which have documented the effects of different types of music on heart rate, blood pressure and respiratory frequency.
They base their study on the one of the features of biological oscillators (i.e. heart rate and breathing rate), that being their ability to synchronise to, or be entrained by, external inputs. For example “auditory inputs have also been shown to produce entrainment of respiratory timing.”
The BMJ summarise:
Bernardi and colleagues studied the effect of different styles and tempos of music on cardiovascular and respiratory control in both musicians and non‐musicians. They found that breathing frequency was increased by musical inputs, and that this increase was proportional to the tempo of the music.
In addition to describing an increase in respiratory frequency, Bernardi and colleagues also noted an increase in heart rate and blood pressure, with the increase again correlated to music tempo.
Whilst they recognise that the physiological reason why this happens is less well understood, this research provides an interesting platform for further studies into the relationship between music and the body.