The expression of our thoughts, emotions and after all of our identity occurs often and above all through the voice. But we are not the only ones! The parrots are widely known for their particular ability to speak, repeating what they hear from us humans, with the aim of interact and strengthen social ties With us. From the point of view physiological They succeed thanks to an organ called Sirinx who is in the bifurcation of the trachea and Vibra playing a role similar to that of our vocal cords. But from the point of view neurological? A recent study conducted by researchers Zetian Yang And Michael Long of New York University would explain how they succeed, revealing an extraordinary similarity between the human brain and that of wavy parrocchetti (Melopsittacus Undulatus), small green and yellow parrots, particularly famous for their ability to imitate the human voice. They even manage to imitate different shades and shades that, in the human brain are regulated by sophisticated neural systems. The study has in fact highlighted how also in the brain of these small feathered there are specific regions that organize and modulate vocalizationsdemonstrating a capacity for flexibility and precision in communication very similar to that which characterizes human beings.
The brain organization of the language of parrocchetti is similar to the human one
Thanks to the integration of specialized areas of the cerebral cortex between sensory inputs, motor commands to accurately regulate the movements of the larynx and other muscles involved in language, we are able to give shape to our words. Apparently, we share this brain complexity even with an unsuspected master of imitations, the Melopsittacus Undulatus, also known as wavy parrocchetto or “budgies“.
In the study published a few days ago in the magazine Nature, thanks to special Neurial high intensity silicon probes The researchers recorded and analyzed the activity of a specific brain area of the parrocchetti, the Central core of the anterior Archopallium (AAC), head of the vocal control. It emerged that the neurons of this nucleus are directly involved in the production of sounds, and, even more interesting, they form a real motor mapvery similar to that present in the human motor cortex responsible for language.
The researchers recorded theneuronal activity in the brain of parrocchetti While these produced different types of vocalizations: from the melodic songs, called “warble”, to simpler and more structured references. The most innovative information observed in this study is that neural activity patterns were extremely coherent and organized: acoustically similar vocalizations corresponded to neural configurations similar, indicating that the brain of the parrocchetto uses a orderly and flexible system, like humanto manage a wide range of complex sounds. In practice, every sound they emit corresponds to the activation of specific neurons.
The researchers also discovered that, unlike singing birds such as the Mandarin Diamond (Lonchura Gutta), which they produce Structured and stereotyped songs Through a sort of neural “bar code” unique for each sound, the brain of the parrocchetti uses one much more flexible scheme. The neurons of the AAC, in fact, are activated on the basis of Specific acoustic propertieslike the tone or the harmonious structure of the sounds, using the same neural patterns to produce different vocalizations, but acoustically similar. This system allows parrocchetti to have a large vocal repertoire and above all adaptablewhich explains their surprising imitation capacity.
The parrots are able to modulate tone and the height of the sound
Subsequently, through sophisticated computational analysishave shown that the neurons of the AAC significantly increased their activity to be Before that during the production of sound, confirming a direct role in the preparation and in the modulation of the voice.
To verify that this activity was specifically motor and not simply hearing, they led Playback experimentsreproducing recordings of the sounds produced by the same parrocchetti themselves: during passive listening, this area activated significantly less than active production, confirming that it is also linked to motor activation.
Another aspect of this study is the discovery of neurons specifically sensitive to “pitch“(Sound height). The researchers also decoded the pitch of the vocalizations of the parrocchetti using simple linear models based on the recorded neural activity.
Future implications and perspectives
These discoveries not only bring the animal world closer to ours, revealing neural strategies common to the basis of voice communicationbut they also open new perspectives To understand and treat ailments of language and communication in the human being. The similarity in the neural strategy used by parrocchetti and humans could in fact inspire New therapeutic techniques o advanced brain-computer interface systems.
