Language disturbances after non-thalamic subcortical stroke: a review of the literature

Language disorders following subcortical non-thalamic stroke show great variability across literature and a well-defined profile in these aphasic disturbances is yet to be established. The lack of recent and consistent literature on the subject complicates the management of subcortical aphasia. The aim of this study is to review the literature describing oral language disturbances following subcortical non-thalamic stoke affecting the basal ganglia and the surrounding white matter. A review of the literature of three databases (PubMed, PsycNet and LLBA), identifying research articles from 1997 to 2015, was completed. The quality of the selected studies was assessed using the Checklist for the assessment of methodological quality. Twenty-two articles met criteria for review and oral language assessment data were extracted for 114 subjects. The results suggest a predominance of deficits in more complex and demanding language levels (ex. discourse, syntax) and in language production (vs comprehension). Rapid recovery is expected, especially for lexical-semantic and receptive deficits. These findings show the importance of a complete oral language evaluation after subcortical stoke and provide recent data relative to expected deficits and recovery to guide clinicians in the management of these patients. They also suggest that a descriptive approach of the deficits may be more efficient and accurate than the use of a traditional classification of aphasia.