A 65-year-old man is brought to the neurology clinic by his family, who are concerned about his recent language difficulties. Two weeks ago, he experienced an ischemic stroke affecting the left posterior superior temporal gyrus. Since the stroke, his family has observed that while he speaks fluently, his sentences often contain incorrect words or nonsensical phrases. For instance, he might say “television” when referring to a “refrigerator.” He also appears to have trouble understanding conversations and following simple instructions. During the clinical examination, his speech is fluent but marked by paraphasic errors, such as saying “table” instead of “chair.” He is unable to repeat simple phrases and struggles to follow commands, indicating a significant comprehension deficit. Which of the following is the most likely diagnosis?
