Humans are remarkably adept at recognizing other human voices, not only for the messages they communicate, but also for social and personal information about the person they are talking with. For example, when we answer the telephone we can easily recognize whether it is someone we know (Mom) or someone we don't (a telemarketer). Listeners also make rapid judgments about a speaker's age, gender and where they are from. This project investigates human behavioral and early brain responses to the recorded spontaneous speech of speakers with the same or different dialects and genders using a neuromagnetic brain imaging technology, magnetoencephalography (MEG). Investigators will examine the rating, identification and discrimination of American English dialect stimuli by listeners while their brain activity is passively recorded. These brain activity data will be correlated with dialect differences and behavioral measures. While there has been considerable work on early neural correlates of prosody, very little work has examined the neural basis of within-and across-category perception of speech characteristics that have real-life importance in areas of prejudice and discrimination. Researchers investigating social aspects of language have had limited access to brain imaging technologies, and consequently this collaborative research will contribute to speech perception, neuromagnetic brain research and sociolinguistics, and will foster new connections between these fields. Moreover, this research has other important social and legal implications because its results will bear directly on how courts can and will interpret automatic neural processes and higher order cognitive processing resulting in discrimination and prejudice.
