Abstract
The human cochlear nucleus (CN) is composed of dorsal and the ventral subdivisions. Neurons of this nucleus are unique because they respond to specific impulses arising from the cochlea. This nucleus and the neurons of the cochlea are continuously exposed to external stimuli and can degenerate with aging. This may be one of the causes of presbycusis—an age related hearing loss. One of the therapeutic interventions for this condition is a brainstem implant. An understanding of the morphology of the CN with aging changes will help making better implants for these patients. In the present study we have investigated the qualitative and quantitative changes in the neuronal and glial population of various sub-divisions of human CN at different ages. Forty one (1st to 9th decade) CN were processed for morphometry and stereology. Although the volume of the nucleus does not change with aging, neuronal number showed significant changes with aging. The data from the current morphometric report may facilitate in understanding the physiology of prebycusis, provide insight for cochlear nuclear implantation and eventually help clinicians to rehabilitate geriatric patients with hearing loss.
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Acknowledgements
The authors would like to acknowledge the help provided by Prof. Alok Thakar of the Department of Otorhinolaryngology and the Department of Forensic Medicine and Toxicology, AIIMS, New Delhi. This work was partially funded by Indian Council of Medical Research, New Delhi (5/8/10-2(oto)/2009-NCD-1).
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Sharma, S., Jacob, T.G., Nag, T.C., Bhardwaj, D.N., Roy, T.S. (2017). Changing Population of Neurons and Glia in the Human Cochlear Nucleus During Aging. In: Rath, P., Sharma, R., Prasad, S. (eds) Topics in Biomedical Gerontology. Springer, Singapore. https://doi.org/10.1007/978-981-10-2155-8_12
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DOI: https://doi.org/10.1007/978-981-10-2155-8_12
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