Linguistic Characteristics of Mandarin-Speaking Huntington's Disease Patients

Objective Linguistic problem is common in Huntington's disease (HD) patients. It has been studied before in native speakers of alphabetic languages, such as English. As a hieroglyphic language, Chinese differs from alphabetic languages in terms of phonology, morphology, semantics and syntax. We aimed to investigate the linguistic characteristics of manifest HD in native speakers of Mandarin. Meanwhile, we expected to explore the linguistic differences associated with cortical or subcortical pathology.Methods Five HD patients and five Alzheimer's disease (AD) patients matched in age, gender, disease course and educational level were enrolled. All the participants were Mandarin native speakers. All finished history inquiry, physical examination, basic test, genetic test and neuropsychological assessment. Language evaluation was performed by Aphasia Battery of Chinese.Results HD patients had a mean disease course of 5.4±2.97 (range, 2-10) years. They showed a linguistic disorder close to transcortical motor aphasia. They exhibited prominent phonological impairment, as well as slight semantic and syntactic abnormality. Tonic errors were found in speech. Character structural errors and substitutions were detected in writing. In comparison, AD patients showed a more severe linguistic impairment, characterized by global aphasia with more semantic errors. Conclusion Mandarin-speaking HD patients have a transcortical motor aphasia-like disturbance with prominent phonological impairment, whereas AD patients have a more severe global aphasia with salient semantic impairment.