Introduction: Autistic spectrum disorder (ASD) is characterized by abnormalities of social interactions, communication, restricted interests and repetitive behavior. Disordered sensory reaction constitutes a striking aspect. Auditory processing disorder (APD) may contribute to their language delay.

Objective: Study the auditory processing and its correlation to language assessment in autistic children.

Cases: 30 children diagnosed with autism according to DSM-IV-TR, 23 boys and 7 girls, mean age 65.37 months.

Methods: Language assessment using Test of Acquired Communication Skills (TACS), Comprehensive Arabic Language Test (CALT). Auditory electrophysiological evaluation using auditory brainstem response (ABR), cortical auditory evoked potentials (CAEPs), results of ABR and CAEPs were compared to norms.

Results: (40%) of cases were hyper-responsive to auditory stimuli. TACS revealed that all cases failed to exceed age of 24 months in social and symbolic domain. Only 5 cases exceeded age of 24 months on language domain, and failed to reach their chronological level in CALT. In ABR, latency of waveV, interpeak latencies III-V, I-V of both ears were prolonged. CAEPs absolute N1c latency was prolonged. N1c amplitude was lower compared to norms. N1c amplitude was higher on right side. Positive correlation was detected between N1c amplitude on right side and language domain of TACS in autistic children.

Conclusions: Autistic children possess immature central auditory nervous system at brainstem and cortical levels, and right hemisphere is the dominant one in processing auditory stimuli. The more immature the auditory processing, the lower language score and more severe the abnormality of CAEPs is.