Da Musically Inclined Bomb

DePauw University's First Year Seminar on Writing about Music

Sunday, December 03, 2006

Musical Rhythm, Linguistic Rhythm, and Humane Evolution

Musical Rhythm, Linguistic Rhythm, and Humane Evolution

By: Aniruddh D. Patel, Neuroscience Institute

Musical Rhythm, Linguistic Rhythm, and Humane Evolution is an article discussing the contrasting interests in the ideas of music shaped by natural selection or developed by cognitive abilities. The article was developed following a similar article discussing the idea of pitch regarding evolution and cognitive skills

The first argument, evolution, which was introduced by Darwin, in 1871, is developed based on the idea that humans have changed and adapted to new concepts to understand music. The second argument, adaptive cognitive skills, established by William James, says music is understood by using skills like thinking, reasoning, remembering, imagining, or learning.

Can music be related to the way we talk? Pitch movement and duration develops in our speech habits early in life. According to evidence discovered by neuropsychology and neuron-imaging, similar parts of the brain are used to group what we say and what we play. However, beats in music are determined by meter and the beats in what we say have no particular timing.

BPS: Innateness

Innateness is defined as being born with a skill or ability. So are we born with BPS? As far as we know, infants do not synchronize their movements to a musical beat at birth. But we can’t be sure they don’t have BPS because they may not be able to physically show it (i.e. they don’t talk.) So to address the theory of “born with natural beat synchronizing” developmental studies must take place. Through testing we would be able discover if the brain is specifically prepared with BPS. If we discover they are not, we can use other studies to determine at what age children or adults gain BPS by monitoring abilities to follow rhythm by clapping, tapping, or bobbing up and down.

BPS: Domain-Specificity

Neuropsychological literature presents two cases of individuals with musical rhythmic disturbance after brain damage. In the first case, the subject’s rhythmical abilities were disruptive but pitch skills were still intact. In the second case, the subject could determine simple differences between rhythms but could not reproduce or evaluate patterns. So, is brain damage disabling areas of the brain that work with musical abilities? No tests have been conducted to examine relations between deficits in BPS and in other basic cognitive skills. But, if such relations could be found it would suggest that BPS is based on the abilities recruited from other brain functions.

BPS: Human-Specificity

Humans are not the only ones who can be studied to discover BPS. As far as we know, animals do not naturally produce music therefore, we can study their patterns to better understand BPS. If an animal could acquire the ability to produce music then it would have used cognitive skills. But, can animals learn BPS? Despite decades of psychology and neuroscience research and development not a single animal has been trained to tap, peck, or move with an auditory beat, so without proper testing we can’t be sure.

However, leading in the favor of natural selection, chimps are capable of producing drumming with their hands and feet when they play which means they can voluntarily produce rhythmic movements on a time scale appropriate for BPS.

Human testing shows rhythms that have a regular beat are associated with increased activity in the basal ganglia, a part of the brain that measures the time intervals between beats. If one assumes that BPS only requires a common brain structure to produce interval timing and motor control then one would expect that chimps would be capable of BPS.

However, we know that BPS requires more. A Relationship between auditory and patterned movements is proved necessary by the fact that just visual rhythms poorly induce BPS in humans. Therefore, we move to vocal learning.

Vocal learning is the act of producing vocal signals to provide feedback. Evolutionary perspective shows that some species have picked up the idea of vocal learning (i.e. humans, parrots, song birds). Humans find vocal learning easy because it’s needed to learn how to speak and verbally survive in our society.

Through research, it has been discovered that vocal learning requires a tight relationship between the auditory input and the motor output in the bird. Neurobiological research shows this tight relationship modifies basal ganglia in the bird’s brain the better it becomes at vocal learning. Birds and mammals have many anatomical relationships in the basal ganglia so does that mean humans have also been modified by natural selection for vocal learning?


At 12/03/2006 7:34 PM, Blogger Kitt_Katt said...

Such a strange article. I can't believe they didn't determine anything.

At 12/03/2006 8:07 PM, Blogger Vera Lynn Waters said...

yea, now that i think about it, the reason i didn't understand the article for so long was because they didn't determine anything. after i understood that, i was mad. a weird and pointless article. i like that you had subtitles to seperate your ideas.

At 12/03/2006 8:45 PM, Blogger Godfather Outlaw said...

great job breaking up this article - and awesome guitar monkey

At 12/03/2006 11:03 PM, Blogger Melissa said...

I had never really thought about how related speech and music are.

At 12/03/2006 11:25 PM, Blogger Nat said...

I thought it was funny that both you and Tommy used a monkey with a guitar in your powerpoint. Good presentation.

At 12/03/2006 11:50 PM, Blogger Andrew said...

it makes it hard to comment about the article if they didn't come to a conclusion, but nicely presented.


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