Date of Award


Degree Type


Degree Name

Master of Science (MS)


Speech, Language, and Hearing Sciences

Committee Chair

Natalya Kaganovich

Committee Member 1

Brandon Keehn

Committee Member 2

Laurence Leonard


Throughout school-age years, speech perception is an important skill that often relies on the child’s ability to combine both auditory and visual information from the speaker. In order to better understand the development of multisensory speech perception during mid-childhood, we analyzed audiovisual word perception in three groups of participants: 8-9-year olds, 11-12-year olds, and adults. Participants matched visually-perceived articulatory movements with corresponding auditory words. In “congruent” trials, the auditory word matched the subsequently presented silent visual articulation. In “incongruent” trials, the words presented differed on the initial phoneme. From this task, we evaluated specific neural components —the N400 and the Late Positive Complex (LPC) — which index the phoneme and whole word level of audiovisual processing, respectively. The results of this experiment were then related to a real-life behavioral speech perception skill, namely, listening to speech-in-noise. Our results suggest that while the LPC becomes adultlike by the age of 11 or 12, the N400 is not fully matured until later in development. In addition, the relation of the LPC to listening to speech-in-noise is stronger earlier in childhood while the relation of the N400 is stronger during later school years and adulthood. Overall, we show that audiovisual processes related to the whole-word level mature earlier in childhood than processes related to the phonological level.