Love of musical harmony is nurture not nature

Our love of music and appreciation of musical harmony is learned and not based on natural ability – a new study by University of Melbourne researchers has found. 

Associate Professor Neil McLachlan from the Melbourne School of Psychological Sciences says previous theories about how we appreciate music were based on the physical properties of sound and the ear itself, leading to a belief in an innate ability to hear harmony.

“Our study shows that musical harmony can be learnt, and it is a matter of training the brain to hear the sounds,” Associate Professor McLachlan says.

“So if you thought the music of some exotic culture (or jazz) sounded like the wailing of cats, it’s simply because you haven’t learnt to listen by their rules.”

The researchers used 66 volunteers with a range of musical training and tested their ability to hear combinations of notes to determine if they found the combinations familiar or pleasing.

“We found that people needed to be familiar with sounds created by combinations of notes before they could hear the individual notes. If they couldn’t find the notes they found the sound dissonant or unpleasant,” he explains.

“This finding overturns centuries of theories that physical properties of the ear determine what we find appealing.”

Co-author on the study Associate Professor Sarah Wilson also from the Melbourne School of Psychological Sciences says the study found trained musicians were much more sensitive to dissonance than non-musicians.

“When they couldn’t find the note, the musicians reported that the sounds were unpleasant, whereas non-musicians were much less sensitive,” Associate Professor Wilson says.

“This highlights the importance of training the brain to like particular variations of combinations of sounds like those found in jazz or rock.”

Depending on their training, a strange chord or a gong sound was accurately pitched and pleasant to some musicians, but impossible to pitch and very unpleasant to others.

“This showed us that even the ability to hear a musical pitch (or note) is learnt,” Associate Professor Wilson says.

To confirm this finding they trained 19 non-musicians to find the pitches of a random selection of western chords. Not only did the participants’ ability to hear notes improve rapidly over 10 short sessions, afterward they reported that the chords they had learnt sounded more pleasant – regardless of how the chords were tuned.

The question of why some combinations of musical notes are heard as pleasant or unpleasant has long been debated.

“The most generally accepted theory of dissonance that’s been with us since the mid-19th century is the Helmholtz’s Roughness theory,” Associate Professor McLachlan says.

The theory is based on a method of musical tuning first proposed by Pythagoras over 2000 years ago, that if we have tunings that vary slightly from simple number ratios of chords, then the harmonics will start to interfere with each other, making them unpleasant to listen to.

Associate Professor McLachlan says the theory was even used to racially discriminate against non-Europeans.

“After proposing that dissonance was caused by physical properties of the ear it was difficult to explain why different cultures preferred different tunings. So some prominent European musicologists proposed that most non-European people were genetically inferior and too insensitive to discern the difference between consonant and dissonant sounds.

“But our latest study shows that appreciation of musical harmony is learnt and not innate,” he says.

Previous studies by these researchers using computer modeling and scans of the brain are consistent with these findings.

“We have shown that for music, beauty is in the brain of the beholder,” Associate Professor McLachlan says.

The study was published in the Journal of Experimental Psychology: General.

www.cmmw.unimelb.edu.au