The Production Study Of Subcortical Aphasia

Objection: To investigate the characteristics and pathogenesis in speech production of the patients with subcortical aphasia, and its theoretical basis of the rehabilitation model.Methods: Using The Standardized Aphasia Battery in Chinese (ABC), we examined 13 thalamic aphasics and 24 basal ganglia aphasics after subcortical cerebral vascular accidents, then compared the performance on production (talk, comprehension, repetition, naming) between these two groups, and investigated the characteristics of language impairment. Then to examine 12 patients of thalamic aphasia and basal ganglia aphasia and analyze the scores of phonological, lexical and syntax, and compared them with 12 normal controls. Statistical analysis was carried out by SPSS 11.5 software.Results: There was no significant difference between thalamic aphasics and the basal ganglia aphasics in comprehension tasks (P>0.05). In the repetition tasks, there was significant difference between the two groups in sentences, and there was no significant difference in word repetition (P>0.05). In the naming tasks, there was significant difference between them in responsive naming (P<0.05) except the visual naming and color naming (P>0.05). The most likely phonological error type in thalamic and basal ganglia aphasia was substitution (27ci/75%, 30ci/68.7%), while the environment errors occured smallest (only 2ci/5.6%, 5ci/8.4%). The lexical error type of thalamic aphasia was dominantly hyponymy (32ci/40.5%) while the type of basal ganglia aphasia was phonemic errors (11ci/26.8%), and the frequencies of occurrence of lexical errors in thalamic aphasia were significantly more than those in basal ganglia aphasia (x2=18.82, p<0.05). In talking tasks, compared with the control group, the scores of the numeral and preposition were significantly lower in the patients with subcortical aphasia (p<0.05), while it was significantly higher in the occuring ratio of simple sentences, affirmative and active sentences (p<0.05).Conclusions: Basal ganglia aphasia group was characterized with lack of speech fluency, occurrence of phonetic paraphasias, mainly preserved repetition and naming. Thalamic aphasia, however, was characterized with fluent output, impaired sentences repetition and naming with predominant lexical paraphasias. The most prominent feature in basal ganglia aphasia was phonetic impairment of language, opposite to thalamic aphasia where lexical- semantic processing seemed to be affected. The production of grammatical morphemes was selectively impaired, and the structure ofthe sentences was too simple in the patients with subcortical aphasia. The different features of language impairment suggested that left subcortical structures contributed to phonological, lexical-semantic and syntax of organization and expression.