Background and purpose: The main features of non-fluent aphasia are inadequate production, limited vocabulary and agrammatism. Such patients have deficits in sentence comprehension and production and their speech is short and telegraphic. In this study, morphological and syntactic errors in speech of non-fluent aphasia were compared with those in healthy subjects.

Materials and methods: A cross-sectional study was performed in 8 patients with non-fluent aphasia and 8 healthy individuals who were matched for age, sex and educational level. The morphological and syntactic structure of speech in healthy subjects and patients were elicited by two tasks (spontaneous speech and pictures description). Data analysis was conducted using the Mann-Whitney test.

Results: In spontaneous speech and pictures description significant differences were observed between healthy subjects and patients in average number of names (P=0.004). The average number of verbs showed significant difference between the two groups only in spontaneous speech (P=0.022). Also, other morphologic and syntactic elements such as the number of content and grammatical words, intransitive and transitive verbs, active and passive verbs, and mean length of utterance were significantly different between patients and healthy controls in both tasks

Conclusion: The results showed inappropriate use of syntactic and morphological structures in sentences by patients. Total number of grammatical words and content words were considerably lower in patients.