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Abstract #3235

Functional Magnetic Resonance Imaging of the Central Auditory System Following Long-Term and Passive Acoustic Exposure at Moderate Sound Pressure Level

Condon Lau1, Jevin W. Zhang2, Joe S. Cheng2, Iris Y. Zhou2, Ed X. Wu2, 3

1Division of Biomedical Engineering, Hong Kong University of Science and Technology, Kowloon, HKSAR, China; 2Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, HKSAR, China; 3Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, HKSAR, China

Recent electrophysiology studies showed that long-term and passive acoustic exposures at moderate sound pressure levels affect auditory cortex function. Such exposures also affect health and task performance. We employ fMRI to study changes in subcortical function in an established rat exposure model. The results show fMRI signal amplitude is lower in the auditory cortex of exposure animals, in agreement with electrophysiology. Signal is higher in the inferior colliculus and medial geniculate body of exposure animals. The subcortical functional changes may reflect changes in corticofugal modulation. Future fMRI studies will further examine subcortical changes following pharmacological manipulations and different exposures.

Keywords

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