Whistled languages represent an experiment of nature to test the widely accepted view that language comprehension is governed by the left hemisphere in an input-invariant manner. Indeed, the left hemisphere does the job for writing as well as atonal, tonal, signed, and clicked languages. The right hemisphere, on the other hand, is specialized to encode acoustic properties like spectral cues, pitch, and melodic lines and plays a role for prosodic communication. Would left hemispheric superiority change, when subjects had to encode a language that is constituted by acoustic properties for which the right hemisphere is specialized? Well, whistled Turkish uses the full lexical and syntactic information of vocal Turkish, and transforms this into whistles to transport complex conversations over kilometers. A group of Biopsychologists from Bochum now tested the comprehension of vocally vs. whistled syllables in native whistle-speaking people of mountainous Northeast Turkey. They discovered that whistled language comprehension relies on symmetric hemispheric contributions, associated with a decrease of left and a relative increase of right hemispheric encoding mechanisms. These results demonstrate that a language that places high demands on right hemisphere-typical acoustical encoding mechanisms creates a radical change in language asymmetries. Thus, language asymmetry patterns are importantly shaped by the physical properties of the lexical input. This paper was featured by many prime media like Science, Scientific American, The Scientist, New York Times, The New Yorker, BBC, Washington Post, CNN, and many more. It is also part of the Science podcast of August 21, 2015.

Güntürkün, O., Güntürkün, M., Hahn, C., Challenging the left hemisphere: Encoding of whistle language modifies brain asymmetries, Current Biol., 2015, 25, R693–R710.