What is the primary characteristic of conduction aphasia as observed in patients?

The primary characteristic of conduction aphasia is indeed fluent speech that is often marked by frequent phonemic errors. Patients with conduction aphasia typically can produce speech that flows smoothly and is grammatically intact, which means they do not struggle to form sentences like those with non-fluent aphasia. However, they experience difficulties in the accuracy of their speech, leading to phonemic paraphasias where they may substitute sounds in words or misorder syllables. This characteristic arises from disruption in the connections between Wernicke's area, responsible for language comprehension, and Broca's area, which is involved in speech production.

In contrast, difficulties in comprehension, non-fluency, and severe repetition deficits would align with other types of aphasia. For instance, non-fluent speech with good comprehension typically points to Broca's aphasia, while fluent speech with poor comprehension aligns with Wernicke's aphasia. Similarly, non-fluent speech with severe repetition deficits highlights conduction aphasia's distinctiveness, where repetition is a hallmark feature, but it is more about the phonemic errors during fluent speech rather than an outright inability to repeat. Thus, fluent speech combined with phonemic errors encapsulates the essence of conduction aphasia.