We are all familiar with the power of music: a song blasts through your ear buds and shoots adrenaline through your body, sending a jolt down your spine, willing your legs to keep running. Or maybe you play a soothing Mozart track to relax after work. There is no denying that music has immense power over our bodies and minds.
How are these invisible and intangible sound waves able to have such a powerful impact on us? The power of music lies in the way that it affects our brains.
To maximize the effectiveness of audio, let’s understand the myriad structures and pathways involved in our brain’s response to music.
Where It All Begins
Sound waves hit the ear’s tympanic membrane and are converted to vibrations. These vibrations produce pressure waves inside the ear. The pressure waves get funneled through the inner ear to the cochlea, a hollow chamber of bone that focuses the pressure waves onto a thin membrane called the Organ of Corti. Tiny hair cells sit on the membrane, and the pressure waves cause these hair cells to release neurotransmitters. The neurotransmitters in turn send electrical impulses along the cochlear nerve to the auditory cortex.
Giving Sound Meaning: The Auditory Cortices
The auditory cortex is the gateway of the listening process. It’s responsible for the processing of these basic audio impulses into meaningful insights for the brain. Neurons in the core of the cortex respond to different types of frequencies, pitches and volumes, while cells in the outer regions process intricate factors such as melody and beat.
The auditory cortex also helps to associate sound with memory. The superior temporal gyrus, associated with memory retrieval, surrounds the auditory cortex and is tightly connected with it. This symbiosis leads to our ability to hold songs and other audio in our working memory.
Two pathways crucial to speech and language functioning are located adjacent to the primary auditory cortex:
Wernicke’s area regulates an individual’s ability to process speech that we hear. Located in the superior temporal gyrus of the temporal lobe, the region is responsible for comprehension of language.
Broca’s area is separately located in the posterior (rear) of the inferior frontal gyrus. At the crossroads of sound organization and speaking regulation, Broca’s area is the well-known site of language production and is responsible for an individual’s movements required to speak.
These signals then get processed by the prefrontal Cortex, the “decision maker” of the brain. The prefrontal cortex takes actions like evaluating the factual words of an ad, and deciding to act on an ad’s message.
Once all these sounds — still in the form of electrical impulses flowing along neurons — are processed into brain language, they are contextualized and start igniting a concrete psychophysical response.
While all sound passes through the auditory cortices, some structures are only involved in specific functions.
Selective Attention and Memory
At the back of the skull is the cerebellum, important for motor functions and for its lesser-praised sensory input duties. Depending on the sound’s pleasantness, the cerebellum can intensify certain neural responses, which we experience as ‘selective attention’. The cerebellum also enables the brain to predict possible incoming audio signals, based on patterns and past sensations.
Sound familiarity is any advertiser’s golden ticket when it comes to ad recognition. This makes the cerebellum, and its ability to selectively amplify pleasant audio, critical to marketers.
The powerhouse of memory, the hippocampus receives fully processed sound inputs primed for retention and links them with other responses of the listener. This solidifies the connection between sound and emotion. This is why hippocampal neurons fire when we hear music that we know: as much as we are listening to it, we are remembering how it made us feel!
Remember that ‘chills-down-the-spine’ feeling we talked about? We can thank the mesolimbic pathway (also known as the reward pathway) for that. The pathway starts with the nuclear accumbens, whose neural network between the hippocampus helps the listener to internalize Pavlovian stimulus-reward relationships. It does this by synthesizing the “happiness” neurotransmitter dopamine.
Unsurprisingly, the NA is thought to be the heart of reward in the brain. This influences drive and goal-directed motor behaviors such as desire for a product, and, via the classical conditioning process, activates during passive listening of ad audio.
The dopamine synthesized in the NA binds with receptors in the striatum. These receptors get activated when we eat good food, enjoy sex, or listen to pleasurable music. Notably, the striatum’s dorsal side is the destination of another circuit, the motivation-inducing glutamatergic pathway, which triggers goal-directed behavior and action responses.
For ads, the amount of dopamine reaching the striatum controls desire to seek out rewards and pursue goals, a crucial checkpoint enabling a listener to purchase a product.
As the destination of the two neurotransmitter pathways — one inducing happiness and the other sparking motivation — the striatum’s regulation of cognition and reward perception is a vital function in transforming a listener into consumer.
Another vital structure for emotional response to music is the amygdala. The amygdala functions like the striatum in that it receives impulses from the auditory cortex and determines the emotional reaction to sounds. The difference, however, is that amygdala activity and striatum activity are thought to be inverse. Activity in the amygdala decreases dramatically when listeners engage with pleasant music and “chills” intensity, When striatum activity is at its highest. As a result, the amygdala is associated with fear and other negative emotions.
Advertisers should seek to inhibit amygdala activity overall, minimizing inhibition and risk-aversion, promoting a more positive emotional response that help make a brand image last in positive light.
The final region regulating emotional response in the brain is the hypothalamus. Upon hearing certain music types, the hypothalamus will increase secretions of adrenaline and oxytocin throughout the brain. Adrenaline controls the “fight or flight” response, while oxytocin is sometimes called “the love hormone,” the catalyst of feelings like empathy.
Starting Like Cacophony, Ending in Euphony
Music has phenomenal impact on our brains. While it may seem like a part of everyday living, once it enters our brains, audio is processed in our brains by fantastically complex pathways and structures to create speech and music. These elicit a vast spectrum of emotional reactions. Understanding these pathways can help marketers use audio more effectively.