Logopenic variant primary progressive aphasia is associated with which brain region?

• A. Left posterior frontal and insular areas
• B. Anterior temporal area
• C. Right temporal area
• D. Left temporoparietal area

Answer: (D)

Logopenic variant PPA shows problems with word retrieval and, especially, repetition due to disruption of phonological working memory in the left temporoparietal region. This area, around the temporoparietal junction including the posterior superior temporal gyrus and inferior parietal lobule, is crucial for maintaining and manipulating phonological information. When it degenerates, people struggle with finding the right sounds and repeating sequences, while single-word comprehension remains relatively preserved early on.

The other regions correspond to different PPA profiles: damage in the left posterior frontal and insular areas is typical of nonfluent/agrammatic PPA with apraxia of speech; the anterior temporal region is linked to semantic variant PPA with impaired word meanings; and the right temporal area is not the usual driver of language-dominant aphasia. Thus, the left temporoparietal area best fits the pattern seen in logopenic variant PPA.