Every time you listen to a piece of music, you're actually giving yourself a deep, full-brain workout.
Anyone who has heard a song knows that the feeling is unlike any other. Neurological research into music comprehension has glimpsed why that might be. A song starts with your ears and ends with the music resonating in some way through all four of the brain's major lobes, producing reactions throughout the body, evoking emotions and memory. Looking more closely at the pathways music takes through the brain only reveals why it's played such a powerful role in human life for so long.
The auditory cortex and beyond. Music doesn't follow one path through the brain in a fixed way, so although some things happen earlier than others, much of it happens simultaneously. The various structures involved with comprehension are constantly relaying information back and forth to one another and processing disparate information simultaneously in order to build one's understanding and response to music.
At the earliest stage, though, the auditory cortex is mainly responsible for taking the music you hear and parsing the most rudimentary features of the music, such as pitch and volume. It works with the cerebellum to break down a stream of musical information into its component parts: pitch, timbre, spatial location and duration. That information is processed by higher-order brain structures, which analyze and broaden the music out into a rich experience.
The cerebellum has connections with the amygdala, the brain's emotional center and the frontal lobe, heavily involved in planning and impulse control. It's processed by the mesolimbic system, which is involved in arousal, pleasure and the transmission of neurotransmitters like dopamine. That's where things get interesting.
This dopamine rush — the same we feel when eating a nourishing meal or having sex — produces that indescribable feeling of "the chills" when we listen to an impeccably beautiful section of music. Much of this feeling is caused by activity in the caudate, a subregion of the striatum, which starts creating an anticipatory response up to 15 seconds before the actual emotional climax of a song.
Our most powerful emotional responses are a result of prolonged expectations and a sudden resolution. Our finest composers all had an understanding of this principle, long before the neurology made it clear. And they've utilized techniques to prolong that anticipatory response, such as varying established patterns, modulating tempo and withholding melodic resolutions. The longer an artist withholds the payoff, the more powerful the emotional cascade will be. This strategy has been taken to almost parodic extremes in modern electronic dance music in its reliance on the bass drop, but it derives from the same mechanism composers like Bach and Beethoven have been using for centuries.
Rhythm and the body. According to many accounts of neurological scans, we process rhythm differently than melodies. Researchers led by Michael Thaut of Colorado State University's Center for Biomedical Research in Music found pattern, meter and tempo processing tasks utilized "right, or bilateral, areas of frontal, cingulate, parietal, prefrontal, temporal and cerebellar cortices," while tempo processing "engaged mechanisms subserving somatosensory and premotor information."
This activation in the motor cortex can produce some intriguing effects. Music with groove promotes corticospinal excitability, which causes that irresistible urge to dance. Additionally, music often causes blood to pump into the muscles in our legs, which many believe is what causes people to tap their feet. Rhythms can also cause changes in heart rate and respiratory patterns and can actually cause these internal cycles to sync up with the music. This points towards one of music's possible adaptive functions, as a way to create a sense of connectedness between disparate individuals.
The visual cortex. Surprisingly, the visual cortex is also active during music listening. Daniel Levitin, a leading researcher in music psychology, explained to the Naked Scientists that this is either "because [listeners are] imagining movement or imagining watching a performer."
Fearful reactions to music create an especially powerful activity in the visual cortex as the brain scrambles to visualize the source of fear-inducing sounds. The visual cortex's response may also be responsible for the experience of synesthesia, or seeing the colors of sounds, that many experience.
Either way, the assertion of artists like Beyoncé who claim they "see music" actually has a solid neurological basis.
Memory. Perhaps the strongest reason that people continue to return to music is its effect on memory. Since memories are not stored in the brain in a centralized location but are instead spread throughout neurological pathways, music's ability to activate such large areas of our brain serves as a powerful stimulus for evoking memories. Music's connection to emotion imbues these musical memories with even more significance. In fact, music can be so effective at stimulating memories, it's sometimes used to help patients living with Alzheimer's disease and dementia grasp portions of their former selves.
Listening to music provides a mental workout that few art forms can rival. The way it engages all four lobes of the brain makes it an incredible tool for building neural circuitry in developing minds. And the way it's intertwined with the emotional centers can make it an especially powerful motivating force.
"Our auditory systems, our nervous systems, are indeed exquisitely tuned for music," famed neurologist and music fan Oliver Sacks writes in his book Musicophilia. "How much this is due to the intrinsic characteristics of music itself ... and how much to special resonances, synchronizations, oscillations, mutual excitations or feedbacks in the immensely complex, multi-level neural circuitry that underlies musical perception and replay, we do not yet know."
Everything we uncover only underscores the importance music plays in our lives.