Background and Aim: One of the most important problems of children who suffer from autism is abnormality in receiving and integrating sensory inputs, especially hearing input. It has been shown that brainstem has a key role in receiving, encoding and integrating hearing input. Auditory brainstem response (ABR) is a tool by which we can evaluate this function. The purpose of this study was to assess and to compare autistic and normal children brainstem hearing function.
Materials and Methods: This case-control study was conducted on thirty (58 ears) autistic and thirty (57 ears) normal 6-12 years old children. The children with autism were divided into slight and severe subgroups according to Autism Diagnostic Interview-Revised questionnaire. Click-evoked ABR was recorded and compared between groups.
Results: There was significant difference between two groups V and III wave latencies and I-III and I-V interpeak latencies (p<0.05). In fact, comparison of the results of autism subgroups with normal children indicated that the latencies of the severe subgroup significantly prolonged.
Conclusion: Increasing latencies of ABR waves in severe subgroup maybe due to abnormality in low level of brainstem. Brainstem abnormality may result in exacerbating the symptom of autism. It is therefore suggested that ABR is included in diagnostic test batteries for these patients.

Background and Aim: Autism is a pervasive developmental disorder with several speech disorders such as prosodic and pragmatic impairments. Melodic intonation therapy (MIT) based on Albert et al. model (1973) is a rehabilitation method, developed on prosodic features. The aim of this study was to investigate the effects of MIT on Persian autistic children’s prosody.

Methods: An easy version of MIT, adopted for Persian language was designed by researchers. Then, after a successful pilot study on a 10-years-old boy for one month, 13 subjects were selected for the main study. All the subjects were autistic, male, right-handed, 7-10-years-old Persian children studied for 48 sessions (16 weeks). Background information gathered from the parents by a questionnaire. As pre- and post-test, some assessments about children’s fundamental frequency (Fº) and intensity of the Persian vowel sounds and declarative and interrogative sentences were accomplished. The data analysis was done using Praat and SPSS softwares.

Results: There was a statistically significant increase in acoustic features, such as intensity, and fundamental frequency of declarative and interrogative sentences also all six vowels of Persian, excluding /â/ and /æ/ (p<0.05 for all).

Conclusion: The widely reported unusual prosody in autistic children was quantified by this study, too. In addition, there was convincing evidence of the positive effects of melodic intonation therapy on acoustic features in Persian autistic children.