title: Vowel sound extraction in anterior superior temporal cortex.
abstract: We investigated the functional neuroanatomy of vowel processing. We compared attentive auditory perception of natural German vowels to perception of nonspeech band-passed noise stimuli using functional magnetic resonance imaging (fMRI). More specifically, the mapping in auditory cortex of first and second formants was considered, which spectrally characterize vowels and are linked closely to phonological features. Multiple exemplars of natural German vowels were presented in sequences alternating either mainly along the first formant (e.g., [u]-[o], [i]-[e]) or along the second formant (e.g., [u]-[i], [o]-[e]). In fixed-effects and random-effects analyses, vowel sequences elicited more activation than did nonspeech noise in the anterior superior temporal cortex (aST) bilaterally. Partial segregation of different vowel categories was observed within the activated regions, suggestive of a speech sound mapping across the cortical surface. Our results add to the growing evidence that speech sounds, as one of the behaviorally most relevant classes of auditory objects, are analyzed and categorized in aST. These findings also support the notion of an auditory "what" stream, with highly object-specialized areas anterior to primary auditory cortex.
authors.affiliation: Fachgruppen Psychologie und Linguistik, Universität Konstanz, Konstanz, Germany.
authors.forename: Jonas
authors.initials: J
authors.lastname: Obleser
authors.forename: Henning
authors.initials: H
authors.lastname: Boecker
authors.forename: Alexander
authors.initials: A
authors.lastname: Drzezga
authors.forename: Bernhard
authors.initials: B
authors.lastname: Haslinger
authors.forename: Andreas
authors.initials: A
authors.lastname: Hennenlotter
authors.forename: Michael
authors.initials: M
authors.lastname: Roettinger
authors.forename: Carsten
authors.initials: C
authors.lastname: Eulitz
authors.forename: Josef P
authors.initials: JP
authors.lastname: Rauschecker
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001288:Attention / Q000502:physiology; D001303:Auditory Cortex / Q000033:anatomy & histology / Q000502:physiology*; D001306:Auditory Pathways / Q000033:anatomy & histology / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007802:Language; D007807:Language Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D013067:Speech Perception / Q000502:physiology*; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology*