The perceived musicality of some languages results from dependency relations between vowels within a word. In Turkish, for example, the last syllable in words like "kaplanlar" or "guller" must "harmonize" with the previous vowels.
Similar "dependencies" between words, syllables or musical notes can be found in languages and musical cultures around the world.
The biological question is whether the ability to process dependencies evolved in human cognition along with human language, or is rather a more general skill, also present in other animal species who lack language.
Andrea Ravignani, a PhD candidate at the Department of Cognitive Biology at the University of Vienna, and his colleagues looked for this "dependency detection" ability in squirrel monkeys, small arboreal primates living in Central and South America.
Inspired by the monkeys' natural calls and hearing predispositions, the researchers designed a sort of "musical system" for monkeys. These "musical patterns" had overall acoustic features similar to monkeys' calls, while their structural features mimicked syntactic or phonological patterns like those found in Turkish and many human languages.
Monkeys were first presented with "phrases" containing structural dependencies, and later tested using stimuli either with or without dependencies. Their reactions were measured using the "violation of expectations" paradigm.
Using this paradigm, the scientists found that monkeys reacted more to the "ungrammatical" patterns, demonstrating perception of dependencies.
Primatologist and co-author Ruth Sonnweber said that this kind of experiment is usually done by presenting monkeys with human speech: Designing species-specific, music-like stimuli may have helped the squirrel monkeys' perception.
--ANI (Posted on 14-11-2013)