Patrick P. Gao1,2, Russell W. Chan1,2, Alex T.L. Leong1,2, Celia M. Dong1,2, and Ed X. Wu1,2
1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China, People's Republic of, 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China, People's Republic of
In the auditory system, the midbrain inferior colliculus (IC) receives massive
corticofugal projections, yet their functional implications remain unclear. Previous
studies utilizing single neuron recordings and electrical activation or
cryogenical inactivation of the cortex could not provide a cell-type specific understanding
of the large-scale corticofugal modulation effects. This study combines
auditory and optogenetic fMRI to investigate the corticofugal influences on auditory
midbrain processing. Large-view fMRI was used to monitor the IC noise response during
cell-type specific optogenetic stimulation of the VC. The results demonstrate
the feasibility of this novel approach and show that VC normally facilitates auditory
midbrain responses.
