Ventral language pathway involvement in Logopenic Aphasia and Posterior Cortical Atrophy.
-
1
University of Sydney, Faculty of Health Sciences., Australia
-
2
Massachusetts General Hospital, Harvard Medical School, United States
The logopenic variant of primary progressive aphasia (lvPPA) and posterior cortical atrophy (PCA) are progressive neurocognitive syndromes, often caused by Alzheimer’s disease (AD), that present with distinctive neurocognitive-anatomical profiles. Whereas lvPPA is characterised by prominent language decline and atrophy in the left temporo-parietal junction, PCA exhibits a range of visuo-spatial deficits and bilateral atrophy of the posterior parietal-temporal and occipital cortices. Despite these seemingly clinical-anatomical differences, word-finding difficulties and impaired naming are language deficits often encountered in both syndromes. Those deficits are largely explained by left-sided atrophy of the posterior aspects of the inferior parietal and temporal cortices, but limited information is available on the long-range white matter (WM) tracts that connect areas of maximal grey matter atrophy with intact distant regions. In particular, we investigated microanatomical changes in the Middle Longitudinal (MdLF) and Inferior Longitudinal (ILF) Fascicles, which conform part of the ventral language pathway and connect the posterior portion of the superior temporal gyrus, parietal cortex, and occipital lobes with the anterior temporal pole, a key region for semantic integration. We selected 21 lvPPA, 14 PCA and 23 control participants who underwent diffusion tensor imaging (DTI) tractography to reconstruct the MdLF and ILF and extract tract-specific DTI metrics (fractional anisotropy, radial diffusivity, mean diffusivity and axial diffusivity). Whereas participants with lvPPA had more involvement of the left MdLF and left ILF, the right ILF was more affected in PCA, concordant with the expected pattern of cortical atrophy.
Acknowledgements
C.Leyton is funded by an NHMRC-ARC Dementia Research Development Fellowship
APP1102969.
Keywords:
Aphasia,
Logopenic PPA,
Primary progressive aphasia (ppa),
Posterior cortical atrophy (PCA),
Middle longitudinal fascicle,
Inferior longitudinal fascicle
Conference:
Academy of Aphasia 57th Annual Meeting, Macau, Macao, SAR China, 27 Oct - 29 Oct, 2019.
Presentation Type:
Poster presentation
Topic:
Not eligible for student award
Citation:
Leyton
CE,
Makris
N,
Dickerson
BC and
Collins
J
(2019). Ventral language pathway involvement in Logopenic Aphasia and Posterior Cortical Atrophy..
Front. Hum. Neurosci.
Conference Abstract:
Academy of Aphasia 57th Annual Meeting.
doi: 10.3389/conf.fnhum.2019.01.00057
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
04 May 2019;
Published Online:
09 Oct 2019.
*
Correspondence:
Dr. Cristian E Leyton, University of Sydney, Faculty of Health Sciences., Sydney, NSW, Australia, cristian.leyton@sydney.edu.au