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.