Which type of aphasia is characterized by the ability to produce speech but not comprehend it?

Wernicke's aphasia is characterized primarily by the ability to produce speech fluently while having significant difficulty with comprehension. Individuals with this type of aphasia often speak in long, rambling sentences that may lack meaning or include made-up words. They may not understand language spoken to them, leading to communication that sounds fluent but is nonsensical or disconnected from reality. This condition arises from damage to Wernicke’s area, a region in the brain associated with language comprehension.

In contrast, other types of aphasia focus more on production difficulties or a total loss of both comprehension and production. For example, global aphasia involves severe impairments in both comprehension and speech production, whereas Broca's aphasia primarily affects the ability to produce speech while comprehension remains relatively intact. Motor aphasia, often synonymous with Broca's aphasia, also does not fit the characteristics of being able to produce speech without comprehension. Thus, Wernicke's aphasia is the clear choice given its distinct features centered around the mismatch between fluent speech production and impaired comprehension.