Performance in Specific Language Tasks Correlates With Regional Volume Changes in Progressive Aphasia

Abstract

Performance on specific language tasks corresponds to regional anatomic damage in aphasia owing to neurodegenerative disorders. These language tests might be useful in the differential diagnosis of primary progressive aphasia variants that have been previously associated with damage to corresponding anatomic regions.

Voxel-level comparison of arterial spin-labeled perfusion MRI and FDG-PET in Alzheimer disease

“…While not a central goal of this present study, the inferior frontal/temporal correlation with BNT and dorsal frontoparietal correlation with DSS are consistent with known networks supporting naming and control/working memory processes involved in these psychometric measures. 38,39 That ASL and FDG-PET were able to detect these distinct networks with good agreement between them is further evidence for the similarity between these 2 methodologies. A major limitation of the present study is the small patient cohort, which precludes assessment of correlations with disease severity.…”

Patterns of cortical thinning in the language variants of frontotemporal lobar degeneration

“…In PNFA, the initial clinical feature is often apraxia of speech, 2,24 which has been associated with left insula involvement 24,25 and agrammatism, which has been associated with left inferior frontal lobe damage. 26 Other regions of superior temporal cortex involved in the PNFA group here, in particular the superior temporal sulcus and transverse temporal gyrus, mediate the analysis, transcoding, and short-term storage of speech signals. 27 Damage involving these areas might contribute to impairments of phonologic encoding, working memory, and grammar processing that are often prominent in this group, 8,28 suggesting testable hypotheses for future work.…”

Why are patients with progressive nonfluent aphasia nonfluent?

“…5,6,11,25 This is the hallmark characteristic of this subgroup of PPA. We observed significantly nonfluent speech in a large, semi-structured sample in PNFA.…”

“…The hallmark feature of PNFA is reduced speech fluency. 5,6 In this study, we investigated 3 potential sources of nonfluent speech attributed to PNFA, including grammatic simplifications and errors, 1,5 a motorrelated disorder associated with speech-sound errors known as apraxia of speech (AOS), 3,7 and executive difficulty that limits mental search for words. 8,9 An executive deficit also is seen in patients with FTLD with a disorder of personality and executive functioning known as behavioral-variant frontotemporal dementia (bvFTD).…”