Aphasia is a disorder that affects the area of the brain colloquially known as the language center. This is certainly an oversimplification of how language is processed and produced, but there is a good reason for its name.
It is home to Broca’s Area and Wernicke’s Area. There is a fascinating amount of information to learn about these areas if you are interested in neurolinguistics. For now, I am simply going to show you an example of each to explain how the study of brain trauma has given us insight into how the brain produces language.
Broca’s Area controls the production of speech. Patients with damage to this part of their brain experience difficulty finding the right word, but they can comprehend words and when they do speak, they use the correct word. They are aware that they are having difficulty speaking due to their intact comprehension and often get quite frustrated with themselves. This is sometimes called Non-Fluent Aphasia because of the incoherent, effortful nature of their speech.
Wernicke’s Area controls the perception of speech. This means they have no difficulty producing speech, but that the semantic meanings attached to words are jumbled. If you didn’t know English and you listened to the man in the video below, you would probably assume he was making perfect sense. They often remember chunks of words that go together, which you’ll notice in the video. This type of aphasia is often called Fluent Aphasia. It can appear somewhat like dementia in that they seem to be babbling and don’t comprehend the actual meaning of speech. However, they are unaware that they are making no sense and are perfectly content telling a story.