They explain how the brain processes speech tones

2017/08/25 Etxebeste Aduriz, Egoitz - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Anatomia/Fisiologia

People have a great capacity to detect changes in tone, something essential for communication. Well, neuroscientists at the University of California explain how we detect the tone changes of speech, in a work published in the journal Science.

According to the intonation, the same phrase can have a very different meaning; for example, the phrase can be neutral or ask, and by reinforcing one word or another the meaning changes. To analyze how the brain detects these differences, researchers at the University of California have conducted an experiment with ten volunteers. The volunteers listened to four sentences with the same structure, expressed by three different voices, and each of them in four different intonations. Meanwhile, the activity of a certain area of neoortex was measured using electrodes.

Thus, they observed that some neurons distinguished the three voices according to the tone of each of them. Other neurons, on the other hand, differentiated the four phrases, just as you said, that is, they detected the phonemes of the words. And finally, a third group of neurons differentiated the intonations; both voice and voice, or phrase that was. In addition, the researchers have found that neurons that separate the voices detect the absolute tone of each voice, while those that characterize the intonation detect the relative tone, that is, the tonal changes of the speaker's voice moment.