title: Cortical and subcortical activation with monaural monosyllabic stimulation by functional MRI.
abstract: Few reports have characterized auditory processing in monaural stimulation, which is important to the understanding of auditory brain activity in subjects with hearing loss. We therefore measured regional brain activity in response to monaural stimulation of 95 dB SPL monosyllables using functional magnetic resonance imaging (fMRI) in subjects with normal hearing and five with unilateral deafness as controls for 'cross-hearing'. Images were analyzed by statistical parametric mapping software. In subjects without hearing loss, the stimuli elicited cortical activation in the primary auditory (BA 41) and auditory association regions (BA 42, 22), particularly contralaterally where extent of activation was approximately 2.5 times the ipsilateral extent. All patients with profound unilateral deafness showed no statistically apparent response in the primary auditory and auditory association regions, ruling out an important influence from cross-hearing. We found fMRI to be a useful technique for analysis of auditory processing that should be applicable to patients with various hearing abnormalities.
authors.affiliation: Department of Otolaryngology, Shiga University of Medical Science, Seta, Otsu, Japan. miki@belle.shiga-med.ac.jp
authors.forename: Mikio
authors.initials: M
authors.lastname: Suzuki
authors.forename: Hiroya
authors.initials: H
authors.lastname: Kitano
authors.forename: Tuyoshi
authors.initials: T
authors.lastname: Kitanishi
authors.forename: Ryuta
authors.initials: R
authors.lastname: Itou
authors.forename: Akihiko
authors.initials: A
authors.lastname: Shiino
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishida
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Yazawa
authors.forename: Fumio
authors.initials: F
authors.lastname: Ogawa
authors.forename: Kazutomo
authors.initials: K
authors.lastname: Kitajima
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001303:Auditory Cortex / Q000502:physiology* / Q000503:physiopathology; D001931:Brain Mapping; D003638:Deafness / Q000503:physiopathology; D004423:Ear / Q000502:physiology* / Q000503:physiopathology; D005260:Female; D006309:Hearing / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010700:Phonetics; D012016:Reference Values