Chapter 6~ After Dessert, Crick Was Still Four Seats Away from Me

   Music with a pulse is generally what humans listen to. Pulse within music generally is regular and evenly spaced. The pulse in music causes humans to create expectations in the piece of music they are listening to. Composers use pulse to set up expectations in a piece and then deviate from the expectations to move the listener emotionally. Composers also subdivide the regular beat, accenting certain notes differently than others. Groove is a strong momentum created from beat divisions that rhythmically drives the song. Groove is usually a subtle feature of a song and is best when it does not have a regular pulse. Composers also change the pulse subtlety by changing the dynamics of a song to reflect the emotions of humans. Dynamics consists of how loud or soft a musician should play, tempo changes, and crescendos and decrescendos. The brain uses feature extraction to create a schema or a model of a constant pulse in a song. This can also be called metrical extraction. The brain will then know when a piece of music deviates from the constant pulse whether it be through dynamics or the subdivision of beats. Violations of expectations is what moves humans emotionally when listening to a song.

Different Note Possibilities to Subdivide the Beat

    The cerebellum's functions are timing and the coordination of movements. The cerebellum is the part of the brain that keeps track of the beat to create a schema. Through the studies of Jeremy Schmahmann, it has been concluded that the cerebellum contains many connections to the human emotional centers of the brain, the amygdala and frontal lobe. The question that followed this discovery was,"what is the connection between movement and emotion." Daniel J. Levitin had the opportunity to sit down with Francis Crick and discuss this question. Francis Crick told him, "Look at the connections." Daniel J. Levitin conducted several experiments to measure and analyze the interaction of different brain regions with each other. He discovered that listening to music caused brain regions to become activated in a set order. The first region that was activated was the auditory cortex. The auditory cortex processed the components of the sound. Then the frontal regions of the brain were activated, processing musical structure and producing expectations. A network of regions called the mesolimbic system was activated last, causing the nucleus accumbens to be activated. The cerebellum and basal ganglia were active throughout the process. As a result, dopamine levels increased in the nucleus accumbens and the cerebellum helped regulate emotion because of its connections to the frontal lobes and mesolimbic system.

   Music is a way to improve people's moods. Music imitates some aspects of vocal communication. It activates some of the same regions of the brain that vocal communication does. It also activates regions that are involved with motivation, reward, and emotion. When listening to music, the brain is constantly updating its expectations of what will come next in the song. The cerebellum, through its connections, causes humans to feel delight or happiness when it updates its expectations after a song deviates from the cerebellum's previous expectations. Humans also feel joy when their expectations are correct and the expected beats are played in a given song. The way human react to music is based purely on connections between the different brain regions. A single song can activate the oldest and newest parts of the brain and can activate the regions in the back of the brain, all the way to the front of the brain.