Impact of Severity of Autism on Auditory Behaviour and Receptive Vocabulary in Autism Spectrum Disorder

Auditory processing deficits are common in children and adults who are diagnosed with autism spectrum disorder (ASD). An intuitive yet underexplored hypothesis is that deficits in auditory processing may manifest in auditory sensory behaviours. As a result of irregularities in the domain of auditory processing, deficits in speech and language processing may occur, and studies show that receptive vocabulary deficits are also often present. This study aimed to examine the differences in auditory behaviour and receptive vocabulary between children with lower and higher degrees of severity of autism. The sample included 30 children aged from three years and five months to six years and 11 months. The GARS-3 was used to determine the severity of autism, the Auditory Processing subscale (APS) from the Sensory Profile and the Questionnaire on Auditory Behavior for Children with Autism Spectrum Disorder (QAB-ASD) (constructed for this study) were used to assess auditory behaviour, and the Peabody Picture Vocabulary Test (PPVT) was used to assess receptive vocabulary. The obtained results indicate that children with a higher degree of severity of autism are more prone to exhibiting atypical auditory behaviour. At the same time, no differences in receptive vocabulary development were found between groups. The correlation between receptive vocabulary and auditory behaviour measured by the APS was not found, but it was with the score on the QAB-ASD. The results suggest the impact of the severity of autism on the manifestation of auditory behaviour but not on the receptive vocabulary development in children with ASD.