“The theory can be easily verified by analyzing a language which possesses the full range of physical properties in the perception of which the right brain hemisphere is specialized. We can count ourselves lucky that such a language exists – namely whistled Turkish.”
The team tested 31 inhabitants of Kuṣköy, a village in Turkey, who speak Turkish and whistle it as well. Via headphones, they were presented either whistled or spoken Turkish syllables. In some test runs, they heard different syllables in both ears, in other runs the same syllables. They were asked to state which syllable they had perceived. The left brain hemisphere processes information from the right ear, the right hemisphere from the left ear.
For spoken Turkish, a clear asymmetry emerged: If the participants heard different syllables, they perceived the syllables from the right ear much more frequently – a dominance of the left brain hemisphere. That asymmetry did not exist in whistled Turkish. “The results have shown that brain asymmetries occur at a very early signal processing stage.”
Whistled Turkish contains the same vocabulary and follows the same grammatical rules as Turkish.
“It is simply a different format, in the same way as written and spoken Turkish.” A small group of people in the mountainous north-eastern part of Turkey use whistled language which can be heard over distances of several kilometres.
“Even though I am Turkish, I had, strangely enough, never heard of whistled Turkish. I encountered it in Australia for the first time, when a colleague told me about it,” explains the biopsychologist. “I knew instantly that nature had thus provided the perfect method for verifying the theory regarding asymmetry of language perception.”
