Whistled Turkish uses both sides of brain

Whistled Turkish, a language based on whistles, is unique as it uses both sides of the brain, a new study has found, debunked the theory that the left brain hemisphere is dominant in the processing of all languages.
Whistled Turkish was popular in the old days, before the advent of telephones, in small villages in Turkey as a means for long-distance communication.
In comparison to spoken Turkish, whistled Turkish carries much farther. While whistled-Turkish speakers use normal Turkish at close range, they switch to the whistled form when at a distance of 50 to 90 meters away.
The perception of all spoken languages - including those with clicks - written texts and even sign language involves the left brain hemisphere more strongly than the right one.

The right hemisphere, on the other hand, processes acoustic information via slow frequencies, pitch and melody.
According to the currently commonly held opinion, the asymmetry in language processing is not determined by the physical properties of a given language.

"The theory can be easily verified by analysing a language which possesses the full range of physical properties in the perception of which the right brain hemisphere is specialised," said Onur Gunturkun of Ruhr-University Bochum in Germany.
"We can count ourselves lucky that such a language exists - namely whistled Turkish," Gunturkun said.
The researchers tested 31 inhabitants of Kuskoy, 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.
However, that asymmetry did not exist in whistled Turkish, researchers found.
"The results have shown that brain asymmetries occur at a very early signal processing stage," they said.

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 are," said Gunturkun.
Gunturkun and colleagues also noted that whistled Turkish presented a perfect opportunity to test the notion that language is predominantly a left-brained activity, no matter the physical structure that it takes.
That is because auditory processing of features, including frequency, pitch, and melody - the stuff that whistles are made of - is a job for the right brain.
The study was published in the journal Current Biology.