Left posterior temporal regions are sensitive to auditory categorization. J Cogn Neurosci 2008 Jul;20(7):1174-88
Date
02/21/2008Pubmed ID
18284339Pubmed Central ID
PMC3350814DOI
10.1162/jocn.2008.20081Scopus ID
2-s2.0-45849145399 (requires institutional sign-in at Scopus site) 102 CitationsAbstract
Recent studies suggest that the left superior temporal gyrus and sulcus (LSTG/S) play a role in speech perception, although the precise function of these areas remains unclear. Here, we test the hypothesis that regions in the LSTG/S play a role in the categorization of speech phonemes, irrespective of the acoustic properties of the sounds and prior experience of the listener with them. We examined changes in functional magnetic resonance imaging brain activation related to a perceptual shift from nonphonetic to phonetic analysis of sine-wave speech analogs. Subjects performed an identification task before scanning and a discrimination task during scanning with phonetic (P) and nonphonetic (N) sine-wave sounds, both before (Pre) and after (Post) being exposed to the phonetic properties of the P sounds. Behaviorally, experience with the P sounds induced categorical identification of these sounds. In the PostP > PreP and PostP > PostN contrasts, an area in the posterior LSTG/S was activated. For both P and N sounds, the activation in this region was correlated with the degree of categorical identification in individual subjects. The results suggest that these areas in the posterior LSTG/S are sensitive neither to the acoustic properties of speech nor merely to the presence of phonetic information, but rather to the listener's awareness of category representations for auditory inputs.
Author List
Desai R, Liebenthal E, Waldron E, Binder JRAuthor
Jeffrey R. Binder MD Professor in the Neurology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Acoustic StimulationAdolescent
Adult
Auditory Perception
Brain Mapping
Female
Functional Laterality
Humans
Image Processing, Computer-Assisted
Logistic Models
Magnetic Resonance Imaging
Male
Oxygen
Phonetics
Sound Spectrography
Temporal Lobe
