Summary
This area is involved in retrieving the meaning of words. It is also important in other aspects of language, such as reciting sentences, forming sentences and matching words according to their meaning.
Function
This area is involved in retrieving the meaning of words during reading. It becomes active during a number of different tasks. These include tasks that involve trying to find the meaning of a word. But tasks that involve recognising semantic relationships also require activity in this brain area. Such a task involves trying to link words together on the basis of their meaning.
Location
BA 21 is located in the temporal lobe, above BA 20 and below BA 40 and BA 41. The area is also called the middle temporal gyrus.
Fact
This area is also involved in forming sentences and retrieving words with a certain meaning. You can investigate this by asking about a specific word, by mentioning properties of the word. You can think of 'what do you call a glass jar that you put flowers in'.
Patients
Damage to the middle temporal gyrus can lead to conductive aphasia. This is a disorder in which difficulties arise in reciting words and sentences. The patient is able to express himself and to understand sentences. Sometimes, however, the patient has difficulty in finding words, or mixes up the letters and syllables of words.
Author: Myrthe Princen (translated by Thomas von Rein)
Image: Marcel Loeffen