This article is from the public number: Neural Reality (ID: goodness) , author: Siegfried, Photo by Anna Vander Stel on Unsplash
In understanding the origin of human language, animal researchResearch can provide a lot of inspiration.
Speaking is not the only way to express language. After all, verbal information can also be conveyed through gestures, writing, or typing. But speech (Speech) is the most primitive and basic way of human communication. Therefore, understanding the origin of speech can lead to a deeper understanding of language.
Cognitive scientist Tecumseh Fitch (Tecumseh Fitch) believes that the first step in understanding the origin of speech is to be aware of The key factor in the production of spoken language is not limited to humans. In other words, animals in the real world can help us understand how speech, a unique human ability, is produced.
Indeed, only humans possess a complex set of abilities, including vocalization, hearing, and brain processing that can activate rich spoken communication. However, animals can also make complex sounds. For example, parrots are good at imitating human language, and cats can clearly express when they want to eat. Many animals also have a keen hearing, which allows them to distinguish between noise and communication intent.
Thus Fitch believes that even if only humans have complete language capabilities, all aspects of language have “very deep roots of evolution.” “Slight changes in human ancestors’ communication skills have created the complete language capabilities of modern humans.”
Animals and humans are similar
Many terrestrial vertebrates, namely tetrapods (mammals, birds, amphibians and reptiles) also have hearing and The physiological structure of spoken language. Many life forms on the tree of life have anatomical mechanisms to express and perceive spoken language.
But Fitch said that what transcends distant ancestors lies in the neural circuits that the brain has evolved to adapt to unique language expressions.
At the anatomical level, linguists have tried to explain human special language skills. Just as the thumb is opposed to the other four fingers, we can use the tool flexibly; some experts believe that due to the low throat of the vocal tract
Studies have evolved clues to language evolution by studying evolutionary trees, a group of species with the same lineage. Many features of human speech and hearing have been found in all tetrapods, including mammals, reptiles, and amphibians. Of particular note are the homologous and similar traits. All mammals have three cartilage in the middle ear, a homologous trait inherited from the same ancestor. The neural connections that are particularly important for vocalization in some songbird brains may be similar to the neural connections associated with language in the human brain. These neural connections have evolved independently in different lineages, but they are all important for language generation. W.T.Fitch / AR Linguistics 2018
In addition, parrots and many other birds, some bats, and even elephants can mimic the sound. Therefore, the uniqueness of human language is not just about its ability to speak . Taking this evidence into account, the vocal and auditory abilities of various animals are a prelude to the successful evolution of language by humans. It reveals that humans do not acquire speech capabilities through new vocal and hearing structures, but rather new neural connections that control vocal organs.
After all, language is more than making sounds and perceiving sounds. The speaker’s brain must decide what sound to make to give instructions to the vocal organ. At the same time, the listener’s brain must be able to decode the auditory signal and then issue a command to respond.
— Pete Reynolds
This vocal control is different from random noise. The brains of most animals have “instinctive barking” neural circuits, such as dog barking, bird salamander, and seagull squawking. Even humans have this instinct to make sounds, such as crying, laughing, and screaming. As Fitch said, in primates, “
The most popular hypothesis today is that This ability is related to the special connection between spoken and hearing-related brain regions.
In humans and other mammals, the instinctual call originates from direct signals in the brainstem. It spontaneously suppresses and produces signals from the cortex. (most of the brain Developed outer cortex) . Unlike other animals, Human cortex neurons are directly connected to neurons that control the laryngeal muscles. Some neurons in the ape and monkey’s cerebral cortex are connected to neurons that control the lips and tongue, but do not communicate with the laryngeal muscles. (Human brain The neural circuits that connect the auditory cortex and motor cortex are also much more developed) .
There is also a view that this direct neural connection explains why other “talking” species can speak human languages, such as parrots and other songbirds that can learn new speech. These species have similar direct neural connections to their vocal organs, and birds that do not learn new speech do not.
Neural Reality (ID: neurality) , author: Siegfried