- Location: Wilson Hall • 111 21St Ave S • Nashville, TN 37240
- Room: 115
- Contact: Angel Gaither
- Email: firstname.lastname@example.org
- Phone: 615-322-0080
- Website: https://www.vanderbilt.edu/psychological_sciences/events/index.php
- Audience: Free and Open to the Public
Stephen M. Wilson, PhD
Department of Hearing and Speech Sciences
Vanderbilt University Medical Center
"Language regions of the temporal lobe"
In this talk, I will present three recent fMRI/MVPA studies from our lab that have aimed to clarify the functional neuroanatomy of the language regions of the temporal lobe. In the first study, we found that in primary auditory cortex, speech sounds are represented in terms of acoustic features; in particular, vowels are represented with respect to their formants (peaks in the frequency spectra that distinguish one vowel from another). This indicates that cortical encoding of vowels is scaffolded on tonotopy, a fundamental organizing principle of auditory cortex that is not language-specific. In the second study, we found that these representations of vowels in primary auditory cortex are in fact not strictly veridical, but rather are warped by linguistic experience. Specifically, we showed that distinctions that are linguistically meaningful because they cross a phonemic category boundary are neurally enhanced relative to physically equivalent distinctions that do not cross a category boundary. Third, we used spoken and written language stimuli to parcellate downstream language regions in the superior temporal sulcus. We found that this deep sulcus contains a heterogeneous set of language regions with distinct response profiles. We identified at least five regions involved in a range of linguistic processes, from representation of phonological and orthographic word forms, to amodal lexical nodes, to higher level syntactic and semantic functions.