Morphosemantic Treatment of Inflection of Verb Tense in Persian-speaking aphasic Patients with agrammatism: A Single-Subject Study

Background: The production of verb inflection, especially tense marking, is commonly impaired in persons with agrammatic aphasia. In Persian, verbs are inflected in three tenses of the past, present and future and play a key role in the sentence. A group of theories attributes verb inflection errors to syntactic or semantic defects in sentence formulation.Aims: The present study intends to investigate the effect of morphosemantic treatment on the inflection of regular and irregular verbs in the past, present and future tenses in Persian-speaking agrammatic participants.Methods & procedure: A single-subject study with ABA design was performed to evaluate the effect of morphosemantic treatment on four Persian-speaking agrammatic participants. The percentage of correct verb inflection in the training and control verbs was measured and also the graph examination of level, slope of trend, and C statistic, ۲-standard deviation band, effect size (percentage of non-overlapping data), and d statistic were used to analyze the data.Outcomes & Results: All participants demonstrated significant improvement in the trained tenses and generalized to the production of tense morphology on untrained verbs. The effect of therapy was maintained for a three-week follow-up. Also, the morphosemantic intervention was associated with an increase in most of the narrative measures in the picture description and free play tasks.Conclusions: Therapy for verb inflection in spontaneous speech is clinically important. The current study demonstrated that morphosemantic intervention can be successfully used for tense marker deficits in Persian-speaking participants with aphasia and agrammatism.

کلیدواژه ها:

Aphasia ، Agrammatism ، Treatment Efficacy ، single-subject