Language is a complex skill. So, there are several areas of the brain responsible for language acquisition. Each of them is highly important and cannot be excluded.
First of all, we need to mention Broca’s area, which is located in the left hemisphere. This one is responsible for speech, namely its production and articulation. So, whenever one articulates ideas or uses words in correct order (both in spoken and written language), this is due to the proper work of this area.
Second goes Wernicke's area. It is located in the posterior superior temporal lobe. It connects to the Broca’s area via a neural pathway. It is responsible for comprehension.
The last one is the angular gyrus, which is located close to other essential brain parts, like parietal lobe (responsible for tactile sensation), occipital lobe (analysis of visual information) or the temporal lobe (processes sounds). This part, due to its location, gives us the opportunity to process various language-related information (auditory, sensory or visual).
Brain damages can seriously hurt the language acquisition, especially if one of the parts mentioned above would be damaged.
Also, during the World War 2, there were experiments on brain damages. Some soldiers, after the battle, had severe impairments of one part of the brain, left or right. Sometimes it led to a death of a hemisphere. Linguists did study the effects of those damages on speech and language acquisition. It appeared that people with a dead left hemisphere use a lot of adjectives and speak a lot. But cannot use verbs. People with a dead right hemisphere created short sentences used loads of verbs, but excluded adjectives.
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