Prolonged sound exposure has different effects on increasing neuronal size

Lu, H.P., Syka, J., Chiu, T.W., & Poon, P.W.F. (2014). Prolonged sound exposure has different effects on increasing neuronal size in the auditory cortex and brainstem. Hearing research, 314, 42-50.
http://www.ncbi.nlm.nih.gov/pubmed/24911238
Authors
H. P. Lu – Department of Physiology, National Cheng Kung University
J. Syka – Institute of Experimental Medicine, ASCR
T. W. Chiu – Department of Biological Science and Technology, National Chiao Tung University
P. W. F. Poon – Department of Physiology, National Cheng Kung University
Keywords
acoustic stimulation, auditory cortex, auditory pathways, brain, cochlear nucleus, hearing, neurons, neuronal plasticity, rats, time factor, sound
Abstract
Here we compared sound-exposure effects on neuronal size in the auditory cortex and the midbrain. A marked increase in neuronal size (%32) was found at the cortex in the high frequency region distant from the exposing tone. The increase in the midbrain was ever larger (%67) and was found in both the low and high frequency regions.Such differential effects of sound-exposure at the auditory centers across cortical and subcortical levels cannot be explained by simple activity-driven change occurring earlier in the brainstem, and might involve function of other structures as for example the descending auditory system.