Neuropsychologia 2018 08 23;117:92-101. Epub 2018 May 23.
Cognitive Neurology & Alzheimer's Disease Center, Northwestern University, Chicago, IL 60611, USA; Department of Neurology, Northwestern University, Chicago, IL 60611, USA; Department of Communications Sciences and Disorders, Northwestern University, Chicago, IL 60611, USA.
The semantic variant of primary progressive aphasia (PPA-S) is diagnosed based on impaired single-word comprehension, but nonverbal impairments in face and object recognition can also be present, particularly in later disease stages. PPA-S is associated with focal atrophy in the left anterior temporal lobe (ATL), often accompanied by a lesser degree of atrophy in the right ATL. According to a dual-route account, the left ATL is critical for verbal access to conceptual knowledge while nonverbal access to conceptual knowledge depends upon the integrity of right ATL. Read More