Discriminating between Auditory and Motor Cortical Responses to Speech and Nonspeech Mouth Sounds

摘要

Several perspectives on speech perception posit a central rolenfor the representation of articulations in speech comprehension,nsupported by evidence for premotor activation when participantsnlisten to speech. However, no experiments have directly testednwhether motor responses mirror the profile of selective auditoryncortical responses to native speech sounds or whether motornand auditory areas respond in different ways to sounds. We usednfMRI to investigate cortical responses to speech and nonspeechnmouth (ingressive click) sounds. Speech sounds activated bilateralnsuperior temporal gyri more than other sounds, a profilennot seen in motor and premotor cortices. These results suggestnthat there are qualitative differences in the ways that temporalnand motor areas are activated by speech and click sounds: Anteriorntemporal lobe areas are sensitive to the acoustic or phoneticnproperties, whereas motor responses may show more generalizednresponses to the acoustic stimuli.