What Happens When We Hear Music

Music has been an art form that has fundamentally influenced and shaped humanity. Music is present in all parts of life, and can be listened to passively or somewhat intensely and closely. We hear it during celebration and times of joy as well as times of sadness or remembrance. Music weaves its way into people's lives in whatever the situation, and can be a tool for relaxing, celebrating, or grieving. It is arguably the most universal language that exists among humans, as you could likely go to any place in the world and bring a song, and the emotion that the song conveys would be universally felt and understood. For me personally, music has taught me so much about culture and history, as I have studied the music of past musicians. Learning how to play music has expanded my creativity and ability to express myself musically. As such a key part of life, you might wonder how exactly music has the powerful effect that it does. How do musical sounds affect our brains, and when you listen to music, how are you responding?

Playing Music Has Incredible Effects on the Brain!

It is important that before the chemical effects of music are discussed, you should have an understanding of how the music enters your head in the first place. Sound waves produced by music enter your ears, where they hit your eardrum to produce vibration that creates electric signals. Sensory nerves carry these electric signals to the stem of your brain, where they are then sent to different cortices of your brain where audio is processed. 

Stimulus to Response

The Chemical Effects of Music

Listening to music releases a chemical called dopamine in the brain, and this is where biology and music really start to collide! Dopamine is synthesized using tyrosine or phenylalanine. Phenylalanine is an amino acid that is used to create the amino acid tyrosine through hydroxylation. Phenylalanine cannot be produced by the body and must be ingested, whereas tyrosine is synthesized via the hydroxylation of phenylalanine. Phenylalanine is turned into tyrosine through a reaction that is catalyzed by phenylalanine hydroxylase. Then, that tyrosine turns into L-Dihydroxyphenylalanine (L-DOPA) in a reaction catalyzed by either tyrosinase or tyrosine hydroxylase. Finally this L-DOPA creates dopamine through a reaction catalyzed by DOPA decarboxylase. Voila! This is the metabolic pathway that leads to the synthesis of dopamine, the chemical released in the brain when we listen to music. 

    

Dopamine Synthesis*

How is it released in the brain, you ask? There are four major pathways in which dopamine travels in your brain. The path that dopamine takes when triggered by music is the mesolimbic dopamine pathway. This pathway deals with the reward/pleasure function of dopamine. The dopamine begins in high levels in a nucleus called the ventral tegmental area, a region that is located in a section of the midbrain. This region sends dopamine to the nucleus accumbens, also known as the NAc. This path from the ventral tegmental area to the NAc is also the path used by dopamine when triggered by other pleasures such as food or drugs. It is important that the activity of this pathway is regulated, because if the NAc is over-stimulated, a person will begin to desire whatever it is that triggers the dopamine rush to the NAc. 

                     

                                       Location of the Nucleus Accumbens

The Greater Effects of Music

Now, being that music has such powerful physical effects on your state of being, it is important to understand the effects that the physical reactions of music have on how you feel and what you think! Dopamine is a chemical commonly associated with feelings of pleasure and reward, and is also released through the use of drugs or even eating food. However, this chemical does not just control mood. Your dopamine levels can impact your kidneys, blood vessels, processing of pain, and even movement. This chemical that transmits signals to different parts of the body is very important to maintain at a healthy level, as too much dopamine in the brain can lead to schizophrenia, and too little dopamine can lead to other disorders such as ADHD. 

The science of music has also led to the discovery of fascinating effects that music can have on people struggling with different illnesses. For example, people suffering from Alzheimer's disease and other illnesses involving memory loss have been shown to respond to music that they might have experienced in their past. It remains stored in their memory, despite the loss of other physical memories. This is because music is stored in memory in a different area of your brain than memories of things besides music. This musical memory region is not affected by many memory-loss diseases including Alzheimer's. The rhythmic aspects of music have also shown the ability to aid the ability to move in patients suffering from Parkinson's disease. These musical benefits demonstrate the deep connection music has to humanity. It can ease our pain, inspire memory when remembrance is difficult, and completely alter our mood through the dopamine it causes to be released. Our connection to music is so fundamental within our brains, and music is often considered the last thing to stick with us in comprehension and memory as we age. It is truly mind-blowing how fundamentally humans are connected to music, and it is no wonder that it exists as somewhat of a global language, played in cultures all across the world.

Jazz Trumpeter Miles Davis

*Arrow in bottom left of image can be ignored, image cropped from original source