Subcortical Aphasia.

Autor: Radanovic M; Laboratorio de Neurociencias (LIM-27), Faculdade de Medicina, Departamento e Instituto de Psiquiatria, Hospital das Clínicas HCFMUSP, Universidade de São Paulo, Rua Dr. Ovídio Pires de Campos, 785, SP, 05403-903, São Paulo, Brazil. marciaradanovic@gmail.com., Almeida VN; Faculdade de Letras, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
Jazyk: angličtina
Zdroj: Current neurology and neuroscience reports [Curr Neurol Neurosci Rep] 2021 Nov 24; Vol. 21 (12), pp. 73. Date of Electronic Publication: 2021 Nov 24.
DOI: 10.1007/s11910-021-01156-5
Abstrakt: Purpose of Review: Subcortical structures have long been thought to play a role in language processing. Increasingly spirited debates on language studies, arising from as early as the nineteenth century, grew remarkably sophisticated as the years pass. In the context of non-thalamic aphasia, a few theoretical frameworks have been laid out. The disconnection hypothesis postulates that basal ganglia insults result in aphasia due to a rupture of connectivity between Broca and Wernicke's areas. A second viewpoint conjectures that the basal ganglia would more directly partake in language processing, and a third stream proclaims that aphasia would stem from cortical deafferentation. On the other hand, thalamic aphasia is more predominantly deemed as a resultant of diaschisis. This article reviews the above topics with recent findings on deep brain stimulation, neurophysiology, and aphasiology.
Recent Findings: The more recent approach conceptualizes non-thalamic aphasias as the offspring of unpredictable cortical hypoperfusion. Regarding the thalamus, there is mounting evidence now pointing to leading contributions of the pulvinar/lateral posterior nucleus and the anterior/ventral anterior thalamus to language disturbances. While the former appears to relate to lexical-semantic indiscrimination, the latter seems to bring about a severe breakdown in word selection and/or spontaneous top-down lexical-semantic operations. The characterization of subcortical aphasias and the role of the basal ganglia and thalamus in language processing continues to pose a challenge. Neuroimaging studies have pointed a path forward, and we believe that more recent methods such as tractography and connectivity studies will significantly expand our knowledge in this particular area of aphasiology.
(© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
Databáze: MEDLINE
Externí odkaz: