Date on Master's Thesis/Doctoral Dissertation


Document Type

Master's Thesis

Degree Name



Communicative Disorders

Degree Program

Communicative Disorders, MS

Committee Chair

Pitts, Teresa

Committee Co-Chair (if applicable)

Miller, Sharon

Committee Member

Miller, Sharon

Committee Member

Smith, Alan

Author's Keywords

synthetic speech; EEG; AAC; neural coding; speech perception; natural speech; neural imaging


The present study examined whether natural and synthetic speech are differentially encoded in the auditory cortex. Auditory event-related potential (ERP) waveforms were elicited by natural and synthetic fricative-vowel stimuli (/sɑ/ and /ʃɑ/) in a passive listening paradigm in adult listeners with normal hearing. ERP response components were compared across conditions. The results indicated that peak latencies to natural speech were significantly earlier than those to synthetic speech. Natural speech also produced significant electrode hemisphere site effects, whereas synthetic speech activated left, midline, and right electrode hemisphere sites equally. Overall, the results suggest that cortical processing of natural and synthetic speech activates distinct neural systems which has important clinical implications for the speech-language pathology field.