The purpose of this project is to describe the encoding of speech sound differences in the human cerebral cortex, specifically, the nature of early acoustic-phonetic analyses that map acoustic cues onto abstract phonetic representations of speech sounds. The methodology involves coupling behavioral testing with two well-established clinical techniques: direct cortical electrical interference and intracarotid sodium amobarbital testing. Preliminary studies confirmed the efficacy of this approach, established a critical role for cortical processing in speech discrimination, and provided the foundation for three working hypotheses: (1) Cortical encoding is differentially sensitive to consonant-vowel, but not to traditional consonant feature differences; (2) Acoustic-phonetic analyses for speech discrimination are also required for auditory access to lexical processing; and (3) Cortical regions critical for speech discrimination are highly localized with lateral left perisylvian cortex. The proposed studies will assist in determining the scope of cortical sensitivity to acoustic-phonetic information and in identifying critical underlying neuroanatomic structures.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29DC003081-02
Application #
2733692
Study Section
Special Emphasis Panel (ZRG1-SEN (06))
Project Start
1997-07-01
Project End
2002-06-30
Budget Start
1998-07-01
Budget End
1999-06-30
Support Year
2
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Johns Hopkins University
Department
Neurology
Type
Schools of Medicine
DUNS #
045911138
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Crone, N E; Boatman, D; Gordon, B et al. (2001) Induced electrocorticographic gamma activity during auditory perception. Brazier Award-winning article, 2001. Clin Neurophysiol 112:565-82
Crone, N E; Hao, L; Hart Jr, J et al. (2001) Electrocorticographic gamma activity during word production in spoken and sign language. Neurology 57:2045-53
Boatman, D; Gordon, B; Hart, J et al. (2000) Transcortical sensory aphasia: revisited and revised. Brain 123 ( Pt 8):1634-42
Boatman, D; Freeman, J; Vining, E et al. (1999) Language recovery after left hemispherectomy in children with late-onset seizures. Ann Neurol 46:579-86
Boatman, D; Hart Jr, J; Lesser, R P et al. (1998) Right hemisphere speech perception revealed by amobarbital injection and electrical interference. Neurology 51:458-64