The goals of this study will be to investigate the synaptic properties of auditory cortical synapses, in order to assess their putative roles in auditory information processing. The broad objectives of this research are to understand the functional contributions of these projections to auditory perception and behavior and how changes in these synaptic properties manifest with age and in disease processes. I have already identified several anatomical and physiological properties of glutamatergic synapses in the central auditory system, which forms the basis for the proposed investigation. This study will utilize an in vitro slice preparation in the mouse, which has been developed for the auditory cortical pathways. Whole-cell recordings in cortical neurons will be used to record responses to minimal electrical stimulation, photostimulation by uncaging of glutamate, and photostimulation of channelrhodopsin expressing fibers in order to characterize their topographic organization and physiological properties. In addition, a novel method of optical imaging of responses revealed by autofluorescence will be employed to help trace the output patterns of auditory cortical projections. Morphological correlates will be sought using intracellular injections of biocytin. The proposed experiments should lead to further insight on the information-bearing roles of the auditory cortical projections, as well as help to establish their relative weights in the organization of central processing in the auditory system.

Public Health Relevance

This study should enhance our knowledge and perspective of the normal modes of information processing in the auditory system. It should provide a foundation for the further exploration of abnormal processing in auditory neurological diseases and aging, which will eventually lead to improved diagnostics and treatments for patients with disorders of the auditory system.

National Institute of Health (NIH)
National Institute on Deafness and Other Communication Disorders (NIDCD)
Small Research Grants (R03)
Project #
Application #
Study Section
Special Emphasis Panel (ZDC1-SRB-Y (56))
Program Officer
Platt, Christopher
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Louisiana State University A&M Col Baton Rouge
Veterinary Sciences
Schools of Veterinary Medicine
Baton Rouge
United States
Zip Code
Fader, Sarah M; Imaizumi, Kazuo; Yanagawa, Yuchio et al. (2016) Wisteria Floribunda Agglutinin-Labeled Perineuronal Nets in the Mouse Inferior Colliculus, Thalamic Reticular Nucleus and Auditory Cortex. Brain Sci 6:
Lee, Charles C (2016) Inhibition of mammillary body neurons by direct activation of Group II metabotropic glutamate receptors. Neurotransmitter (Houst) 3:
Lee, Charles C; Yanagawa, Yuchio; Imaizumi, Kazuo (2015) Commissural functional topography of the inferior colliculus assessed in vitro. Hear Res 328:94-101
Lee, Charles C (2015) Exploring functions for the non-lemniscal auditory thalamus. Front Neural Circuits 9:69
Lee, Charles C; Yanagawa, Yuchio; Imaizumi, Kazuo (2015) Nicotinic alteration of functional thalamocortical topography. Neuroreport 26:688-94
Lee, Charles C (2014) Two types of auditory glutamatergic synapses and their implications for repairing damaged central auditory pathways. Neural Regen Res 9:1000-2
Imaizumi, Kazuo; Lee, Charles C (2014) Frequency transformation in the auditory lemniscal thalamocortical system. Front Neural Circuits 8:75
Venkatadri, Pooja S; Lee, Charles C (2014) Differential expression of mGluR2 in the developing cerebral cortex of the mouse. J Biomed Sci Eng 7:1030-1037
Lee, Charles C; Imaizumi, Kazuo (2013) Functional convergence of thalamic and intrinsic projections to cortical layers 4 and 6. Neurophysiology 45:396-406
Lee, Charles C; Lam, Ying-Wan; Imaizumi, Kazuo et al. (2013) Laser-scanning photostimulation of optogenetically targeted forebrain circuits. J Vis Exp :50915

Showing the most recent 10 out of 17 publications