Award Date


Degree Type


Degree Name

Doctor of Philosophy (PhD)



First Committee Member

Joel Snyder

Second Committee Member

Colleen Parks

Third Committee Member

Erin Hannon

Fourth Committee Member

Alyssa Crittenden

Number of Pages



The processing of semantically meaningful non-speech and speech sounds requires the use of acoustic and higher-order information, such as categorical knowledge and semantic context. Individuals with an autism spectrum disorder (ASD) have been theorized to show enhanced processing of acoustic features and impaired processing of contextual information. The current study investigated how children with and without ASD use acoustic and semantic information during an auditory change detection task and semantic context during a speech-in-noise task. Furthermore, relationships among IQ, the presence of ASD symptoms and the use of acoustic and semantic information across the two tasks were examined among typically developing (TD) children. Results indicated that age-matched--but not IQ-matched--TD controls performed worse overall at the change detection task relative to the ASD group. However, all groups utilized acoustic and semantic information similarly. Results also revealed that all groups utilized semantic information to a greater degree than acoustic information and that all groups displayed an attentional bias to detecting changes that involve the human voice. For the speech-in-noise task, age-matched--but not IQ-matched--TD controls performed better than the ASD group. However, all groups utilized semantic context to the same degree. Regression analyses revealed that IQ or the presence of ASD symptoms did not predict the use of acoustic or semantic information among TD children. In conclusion, children with and without ASD utilize acoustic and semantic information when processing semantically meaningful speech and non-speech sounds during auditory change detection and speech-in-noise processing. Furthermore, a diagnosis of ASD alone does not determine lower performance on complex auditory tasks; rather, lower intellect appears to explain group differences in overall performance.


Acoustic; Auditory scene analysis; Autism spectrum disorders; Non-speech; Semantic processing; Speech


Cognitive Psychology

File Format


File Size

1270 KB

Degree Grantor

University of Nevada, Las Vegas




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